807 results on '"Spollen WG"'
Search Results
202. Genome-wide identification of the glutathione transferase superfamily in the model organism Brachypodium distachyon.
- Author
-
Gallé, Ágnes, Benyó, Dániel, Csiszár, Jolán, and Györgyey, János
- Subjects
GLUTATHIONE transferase ,BRACHYPODIUM ,IDENTIFICATION ,GLUTATHIONE ,METABOLITES - Abstract
The detoxification of harmful metabolites can determine the effectiveness of plant stress responses. Scavenging some of these toxic stress by-products through the reduced form of glutathione is catalysed by members of the glutathione transferase (GST) enzyme superfamily. The involvement of these enzymes was studied in the model organism Brachypodium distachyon (L.) P.Beauv. Bd21 and in its derivative Bd21-3, a more drought tolerant line. Osmotic stress treatment resulted in a decrease in the water potential of both Brachypodium genotypes, the difference between the control and treated plant's ψ
w decreased by the last sampling day in Bd21-3, suggesting some degree of adaptation to the applied osmotic stress. Increased GST activity revealed a severe defence reaction against the harmful imbalance of the redox environment. Screening for the gene sequences led to the identification of 91 full-length or partial GST sequences. Although purple false brome has a relatively small genome, the number of identified GST genes was almost as high as the number predicted in wheat. The estimation of GST expression showed stress-induced differences: higher expression levels or the fast induction of BdGSTF8 , BdGSTU35 and BdGSTU42 gene products presumably indicate a strong detoxification under osmotic stress. To generate stress-tolerant crops it is necessary to understand the plants' defence mechanisms and identify the attendants of these processes, e.g. the genes involved in the stress responses and their phylogenetic variability. The active candidates of these processes are detoxification enzymes such as glutathione transferases (GSTs), which, according to our results, showed higher expression levels or fast induction under osmotic stress in purple false brome. These GST coding sequences, belonging to tau and phi classes (BdGSTF8, BdGSTU35 and BdGSTU42) in Brachypodium lines, may account for high tolerance under soil drought. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
203. Water-deficit responsive microRNAs in the primary root growth zone of maize.
- Author
-
Seeve, Candace M., Sunkar, Ramanjulu, Zheng, Yun, Liu, Li, Liu, Zhijie, McMullen, Michael, Nelson, Sven, Sharp, Robert E., and Oliver, Melvin J.
- Subjects
ROOT growth ,CORN ,HAIRPIN (Genetics) ,GENE regulatory networks ,PLANT growth ,PLANT development ,DEFICIT irrigation - Abstract
Background: MicroRNA-mediated gene regulatory networks play a significant role in plant growth and development and environmental stress responses. Results: We identified 79 microRNAs (miRNAs) and multiple miRNA variants (isomiRs) belonging to 26 miRNA families in the primary root growth zone of maize seedlings grown at one of three water potentials: well-watered (− 0.02 MPa), mild water deficit stress (− 0.3 MPa), and severe water deficit stress (− 1.6 MPa). The abundances of 3 miRNAs (mild stress) and 34 miRNAs representing 17 families (severe stress) were significantly different in water-deficit stressed relative to well-watered controls (FDR < 0.05 and validated by stem loop RT-qPCR). Degradome sequencing revealed 213 miRNA-regulated transcripts and trancriptome profiling revealed that the abundance of 77 (miRNA-regulated) were regulated by water-defecit stress. miR399e,i,j-3p was strongly regulated by water-defcit stress implicating the possibility of nutrient deficiency during stress. Conclusions: We have identified a number of maize miRNAs that respond to specific water deficits applied to the primary root growth zone. We have also identified transcripts that are targets for miRNA regulation in the root growth zone under water-deficit stress. The miR399e,i,j-3p that is known to regulate phosphate uptake in response to nutrient deficiencies responds to water-deficit stress, however, at the seedling stage the seed provides adequate nutrients for root growth thus miR399e,i,j-3p may play a separate role in water-deficit responses. A water-deficit regulated maize transcript, similar to known miR399 target mimics, was identified and we hypothesized that it is another regulatory player, moderating the role of miR399e,i,j-3p, in primary root growth zone water deficit responses. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
204. The Microbiome and Prostate Cancer Risk.
- Author
-
Wheeler, Karen M. and Liss, Michael A.
- Abstract
Purpose of the Review: There is an abundance of evidence that the human microbiome plays an important and nuanced role in controlling human metabolism, immunity, and cancer. Herein we aim to review the most current research looking at prostate cancer and its link with the gut and genitourinary microbiome. Recent Findings Summary: There is now a host of evidence for a unique genitourinary (GU) microbiome. The prostate microbiota, to include viral, bacterial, fungal, and parasitic contributions, as assessed from formalin-fixed tissue is described nicely in the study by Banerjee et al. Further hierarchical analysis by this group found a unique microbiome signature for higher Gleason score cancers and validation PCR studies noted a marked number of viral genomic insertions into host DNA. Shretha et al. also recently established unique GU microbiomes in patients with prostate cancer or benign prostate pathology based on urine samples. The gut microbiome likely also has an indirect but significant role in prostate cancer development and treatment. Liss et al. and Golombos et al. found significant associations between specific gut microbiota and prostate cancer. Interestingly, the balance of inflammatory and anti-inflammatory bacterial lipopolysaccharides, production of bile salts, and metabolism of dietary fiber to short chain fatty acids all likely play important roles in creating systemic pro- or anti-carcinogenic states. In terms of prostate cancer treatment effects, Sfanos et al. noted a unique microbial signature in patients undergoing oral androgen deprivation therapy (ADT) as compared with prostate cancer patients not on ADT. Patients undergoing ADT also had enrichment of bacterial metabolic pathways promoting androgen synthesis. Together, these studies have identified a unique GU microbiome and linked both the GU microbiome and unique gut microbial signatures with prostate cancer and prostate cancer treatments. Whether this information can be used in cancer prevention, treatment, or diagnosis are areas of ongoing and active research. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
205. Identification and functional analysis of proteins in response to light intensity, temperature and water potential in Brassica rapa hypocotyl.
- Author
-
Wang, Hongfei and Shang, Qingmao
- Subjects
LIGHT intensity ,WATER temperature ,PROTEIN analysis ,FUNCTIONAL analysis ,BRASSICA ,BACTERIAL cell walls - Abstract
Hypocotyl elongation is an early event in plant growth and development and is sensitive to fluctuations in light, temperature, water potential and nutrients. Most research on hypocotyl elongation has focused on the regulatory mechanism of a single environment factor. However, information about combined effects of multi‐environment factors remains unavailable, and overlapping sites of the environmental factors signaling pathways in the regulation of hypocotyl elongation remain unclear. To identify how cross‐talks among light intensity, temperature and water potential regulate hypocotyl elongation in Brassica rapa L. ssp. chinesis, a comprehensive isobaric tag for relative and absolute quantitation‐based proteomic approach was adopted. In total, 7259 proteins were quantified, and 378 differentially expressed proteins (DEPs) were responsive to all three environmental factors. The DEPs were involved in a variety of biochemical processes, including signal transduction, cytoskeletal organization, carbohydrate metabolism, cell wall organization, protein modification and transport. The DEPs did not function in isolation, but acted in a large and complex interaction network to affect hypocotyl elongation. Among the DEPs, phyB was outstanding for its significant fold change in quantity and complex interaction networks with other proteins. In addition, changes of sensitivity to environmental factors in phyB‐9 suggested a key role in the regulation of hypocotyl elongation. Overall, the data presented in this study show a profile of proteins interaction network in response to light intensity, temperature and water potential and provides molecular basis of hypocotyl elongation in B. rapa. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
206. Effect of drought stress on the expression of genes linked to antioxidant enzymatic activity in landraces of Zea mays L. and Pennisetum glaucum (L.) R. Br.
- Author
-
Iwuala, Emmanuel, Odjegba, Victor, Ajiboye, Abiodun, Umebese, Caroline, Sharma, Vinay, and Alam, Afroz
- Published
- 2019
- Full Text
- View/download PDF
207. The ABA receptor-like gene VyPYL9 from drought-resistance wild grapevine confers drought tolerance and ABA hypersensitivity in Arabidopsis.
- Author
-
Liu, Jie, Zhao, Feng-Li, Guo, Ye, Fan, Xiu-cai, Wang, Yue-jin, and Wen, Ying-Qiang
- Abstract
The PYR/PYL/RCAR (hereafter referred to PYLs) proteins, which act as abscisic acid (ABA) receptors, have been reported to play a crucial role in response to drought stress. In this study, we used a drought-resistant accession of the wild Chinese grapevine, Vitis yeshanensis-'Yanshan-1', as a model to understand the function of PYLs in grape and other fruit crops. We cloned six PYL genes from V. yeshanensis. Phylogenetic analysis showed that the encoded proteins could be classified into three subfamilies. All six grapevine PYL proteins contained conserved amino acids at positions implicated in 'gate-and-latch' mechanism of ABA binding and in the interaction with PP2C proteins. Gene expression profiles of VyPYLs in various tissues of 'Yanshan-1' plants revealed they were relatively strongly expressed in old leaves compared to young leaves. Analysis of the subcellular localization of the VyPYL proteins showed that they were localized in the cytoplasm and the nucleus. Yeast two-hybrid assays revealed that six VyPYL proteins selectively interacted with three VyPP2C proteins in an ABA-dependent or ABA-independent manner. Expression of one of the genes, VyPYL9, was induced by exogenous ABA and drought conditions. Heterologous expression of VyPYL9 in Arabidopsis enhanced ABA sensitivity during seed germination and primary root growth. Moreover, VyPYL9-expressing Arabidopsis plants showed enhanced drought tolerance, and this was associated with decreased water loss and increased activity of antioxidant defense systems. In addition, we found that ABA promoted leaf senescence in Arabidopsis plants expressing VyPYL9. Taken together, our results suggest that VyPYL9 may be involved in response of grapevine to drought stress via the ABA signaling pathway. Key message: VyPYL9-expressing Arabidopsis plants showed enhanced drought tolerance, and this was associated with decreased water loss and increased activity of antioxidant defense systems. In addition, we found that ABA promoted leaf senescence in Arabidopsis plants expressing VyPYL9. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
208. Can pyraclostrobin and epoxiconazole protect conventional and stay-green maize varieties grown under drought stress?
- Author
-
Sulewska, Hanna, Ratajczak, Karolina, Panasiewicz, Katarzyna, and Kalaji, Hazem M.
- Abstract
Risks associated with drought are increasing and are a global problem. Therefore, there is a need for new solutions for the safe production of food, while maintaining respect for the environment. Fungicides are designed to protect maize plants against disease, but some of the active substances used in preparations can also promote plant growth, which is known as the 'physiological effect'. However, there is a paucity of information as to how some of the 'new generation' fungicides act in stimulating grain yield in plants under abiotic stress, especially drought. Therefore, the effects of these products on conventional and stay-green maize varieties need to be better understood in order to reduce losses caused by droughts and to maximize production. In this study, the effect of a pyraclostrobin + epoxiconazole fungicide preparation on maize plants was evaluated at different times after spraying; during induced drought conditions and again during the regeneration process of the plants. The preparation was applied to 'KWS 1325' (conventional) and 'Ambrosini' (stay-green) varieties at the recommended dose, three times in greenhouse conditions. Plant gas exchange, plant water use efficiency, chlorophyll fluorescence and fresh and dry plant biomass were evaluated. The pyraclostrobin + epoxiconazole preparation increased stomatal conductance and photosynthesis intensity in the 'Ambrosini' plants. When maintained under a high light intensity, the variety used increased efficiency and exchanged excessive energy in the form of thermal energy to protect the maize leaf from light-induced damage under drought stress. Plant photosynthetic efficiency (ETR and Yield parameters) during drought stress and after regeneration was significantly higher in treated plants than in the controls. Thus, the beneficial effects on the physiology of the maize varieties grown under drought stress from the fungicide application are significant for farmers and growers. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
209. A novel QTL QTrl.saw-2D.2 associated with the total root length identified by linkage and association analyses in wheat (Triticum aestivum L.).
- Author
-
Zheng, Xingwei, Qiao, Ling, Zhao, Jiajia, Zheng, Jun, Wen, Xiaojie, Zhang, Xiaojun, Li, Xin, Zhang, Shuwei, Yang, Zujun, Chang, Zhijian, and Chen, Jianli
- Subjects
WHEAT ,COMPARATIVE genomics ,ROOT development ,DROUGHT tolerance - Abstract
Main conclusion: In wheat, a QTL QTrl.saw-2D.2 associated with the total root length was identified, presumably containing genes closely related to root development. A mapping population of 184 recombinant inbred lines derived from the cross SY95-71 × CH7034 was used to map QTL for seedling root characteristics in hydroponic culture (HC) and in soil-filled pot (SP) methods. Four traits, including maximum root length (MRL), root number (RN), total length (TRL), and root diameter (RD) were measured and used in QTL analyses. A total of 33 QTL for the four root traits were detected, 17 QTLs for TRL, six for RN, seven for MRL, and three for RD. Seven QTL were detected in both HC and SP methods, which explained 7–18% phenotypic variation. One QTL QTrl.saw-2D.2 detected in both HC and SP methods was also validated in another population comprised of 215 diverse lines. This QTL is a novel QTL that explained the highest phenotypic variation 18% in all QTL identified in the present study. Based on candidate gene and comparative genomics analyses, the QTL QTrl.saw-2D.2 may contain genes closely related to root development in wheat (Triticum aestivum L.). The two candidate genes were proposed to explore in future studies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
210. Populus trichocarpa clade A PP2C protein phosphatases: their stress-induced expression patterns, interactions in core abscisic acid signaling, and potential for regulation of growth and development.
- Author
-
Rigoulot, Stephen B., Petzold, H. Earl, Williams, Sarah P., Brunner, Amy M., and Beers, Eric P.
- Abstract
Key message: Overexpression of the poplar PP2C protein phosphatase gene PtrHAB2 resulted in increased tree height and altered leaf morphology and phyllotaxy, implicating PP2C phosphatases as growth regulators functioning under favorable conditions. We identified and studied Populus trichocarpa genes, PtrHAB1 through PtrHAB15, belonging to the clade A PP2C family of protein phosphatases known to regulate abscisic acid (ABA) signaling. PtrHAB1 through PtrHAB3 and PtrHAB12 through PtrHAB15 were the most highly expressed genes under non-stress conditions. The poplar PP2C genes were differentially regulated by drought treatments. Expression of PtrHAB1 through PtrHAB3 was unchanged or downregulated in response to drought, while all other PtrHAB genes were weakly to strongly upregulated in response to drought stress treatments. Yeast two-hybrid assays involving seven ABA receptor proteins (PtrRCAR) against 12 PtrHAB proteins detected 51 interactions involving eight PP2Cs and all PtrRCAR proteins with 22 interactions requiring the addition of ABA. PtrHAB2, PtrHAB12, PtrHAB13 and PtrHAB14 also interacted with the sucrose non-fermenting related kinase 2 proteins PtrSnRK2.10 and PtrSnRK2.11, supporting conservation of a SnRK2 signaling cascade regulated by PP2C in poplar. Additionally, PtrHAB2, PtrHAB12, PtrHAB13 and PtrHAB14 interacted with the mitogen-activated protein kinase protein PtrMPK7. Due to its interactions with PtrSnRK2 and PtrMPK7 proteins, and its reduced expression during drought stress, PtrHAB2 was overexpressed in poplar to test its potential as a growth regulator under non-stress conditions. 35S::PtrHAB2 transgenics exhibited increased growth rate for a majority of transgenic events and alterations in leaf phyllotaxy and morphology. These results indicate that PP2Cs have additional roles which extend beyond canonical ABA signaling, possibly coordinating plant growth and development in response to environmental conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
211. How root traits would be affected by soybean yield improvement? An examination of historical cultivars grafted with record-yield cultivar scion.
- Author
-
Li, Shengyou, Wang, Wenbin, Cao, Yongqiang, Wang, Changling, Yan, Chunjuan, Dong, Lijie, Wu, Lishi, Xie, Futi, and Song, Shuhong
- Subjects
SOYBEAN ,CULTIVARS ,GRAIN yields ,BIOMASS - Abstract
Background and aims: During historical yield improvement in soybean, breeders have seldom considered selection for root traits, generally focusing selection on yield traits. Yet, it is not known how root traits of historical cultivars would be altered if their shoot functions and grain yields were largely improved. Here we investigated the influence of record-yield soybean cultivars L14 and Z35 as scions on root traits of historical cultivars. Methods: A total of 11 cultivars, released in different decades, were used to graft with L14 or Z35 scions. Some morphological and physiological traits were measured in the pot-culture experiments. Results: During grain-filling stage, the scions of L14 and Z35 had greater photosynthetic capacity, seed biomass and seed starch accumulation than those of other cultivars. Grafting of cultivars with L14 and Z35 scions resulted in significant decreases in root biomass, root-shoot ratio, root starch accumulation and root morphological traits compared with non-grafts or self-grafts. The genetic gain for these root traits of cultivars released from 1966 to 2006 increased by grafting record-yield cultivars scions, while that of grain yield and nutrient accumulation decreased. Conclusions: Our results revealed the uncoordinated improvement between roots and shoots during historical breeding in soybean. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
212. How Do Different Watering Regimes Affect the Growth, Chlorophyll Fluorescence, Phytohormone, and Phenolic Acid Content of Greenhouse-Grown Ceratotheca triloba?
- Author
-
Masondo, Nqobile A., Aremu, Adeyemi O., Kulkarni, Manoj G., Petřík, Ivan, Plačková, Lenka, Šubrtová, Michaela, Novák, Ondřej, Grúz, Jiri, Doležal, Karel, Strnad, Miroslav, Finnie, Jeffrey F., and Van Staden, Johannes
- Subjects
CHLOROPHYLL spectra ,PHENOLIC acids ,CYTOKININS ,WATER supply ,ABSCISIC acid ,PLANT-water relationships - Abstract
We evaluated the effect of different watering regimes on the growth, chlorophyll fluorescence, phytohormones, and phenolic acids in Ceratotheca triloba (Bernh.) Hook.f., a commonly consumed African indigenous leafy vegetable. The study was conducted in the greenhouse under different watering regimes [seven (daily); three (thrice); two (twice); one (once) day(s) per week] for a period of 2 and 4-months. In each pot (7.5 cm diameter; 150 ml volume), 50 ml of water was applied per treatment. At the end of the experiment, plant growth, chlorophyll fluorescence, phytohormones, and phenolic acids were determined. A decrease in water availability resulted in a consistent decline in plant growth after a 4-month growth period. The severity of reduced water availability was more noticeable in plants watered once a week with a 1.4-fold reduction in growth and quantum efficiency of PSII (Fv/Fm) value of 0.80. The significant decline in growth and chlorophyll fluorescence was probably due to the increased production of abscisic acid (ABA) and cytokinin (CK) content together with the detected phytohormones in plants with restricted water supply. Furthermore, plants watered once a week had a trade-off between growth and phenolic acid production, with significantly higher (threefolds) concentrations of vanillic, ferulic, caffeic, and 4-coumaric acids in 4-month-old plants. Even though C. triloba grew best in well-watered soil, the plant had the potential to adapt and survive in soils with limited water supply for longer periods of growth. These findings suggest that regulation of phytohormones and phenolic acids played an important role in improving the growth of C. triloba under limited water conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
213. Association of breast and gut microbiota dysbiosis and the risk of breast cancer: a case-control clinical study.
- Author
-
Plaza-Díaz, Julio, Álvarez-Mercado, Ana I., Ruiz-Marín, Carmen M, Reina-Pérez, Iris, Pérez-Alonso, Alejandro J., Sánchez-Andujar, María Belén, Torné, Pablo, Gallart-Aragón, Tania, Sánchez-Barrón, María Teresa, Reyes Lartategui, Saturnino, García, Federico, Chueca, Natalia, Moreno-Delgado, Ana, Torres-Martínez, Katia, Sáez-Lara, María José, Robles-Sánchez, Cándido, Fernández, Mariana F., and Fontana, Luis
- Subjects
BREAST cancer ,POLLUTANTS ,BREAST ,ENDOCRINE disruptors ,CASE-control method - Abstract
Background: Breast cancer ranks first in women, and is the second cause of death in this gender. In addition to genetics, the environment contributes to the development of the disease, although the factors involved are not well known. Among the latter is the influence of microorganisms and, therefore, attention is recently being paid to the mammary microbiota. We hypothesize that the risk of breast cancer could be associated with the composition and functionality of the mammary/gut microbiota, and that exposure to environmental contaminants (endocrine disruptors, EDCs) might contribute to alter these microbiota.Methods: We describe a case-control clinical study that will be performed in women between 25 and 70 years of age. Cases will be women diagnosed and surgically intervened of breast cancer (stages I and II). Women with antecedents of cancer or advanced tumor stage (metastasis), or who have received antibiotic treatment within a period of 3 months prior to recruitment, or any neoadjuvant therapy, will be excluded. Controls will be women surgically intervened of breast augmentation or reduction. Women with oncological, gynecological or endocrine history, and those who have received antibiotic treatment within a period of 3 months prior to recruitment will also be excluded. Blood, urine, breast tissue and stool samples will be collected. Data regarding anthropometric, sociodemographic, reproductive history, tumor features and dietary habits will be gathered. Metabolomic studies will be carried out in stool and breast tissue samples. Metagenomic studies will also be performed in stool and breast tissue samples to ascertain the viral, fungal, bacterial and archaea populations of the microbiota. Quantitation of estrogens, estrogen metabolites and EDCs in samples of serum, urine and breast tissue will also be performed.Discussion: This is the first time that the contribution of bacteria, archaea, viruses and fungi together with their alteration by environmental contaminants to the risk of breast cancer will be evaluated in the same study. Results obtained could contribute to elucidate risk factors, improve the prognosis, as well as to propose novel intervention studies in this disease.Trial Registration: ClinicalTrials.gov NCT03885648 , 03/25/2019. Retrospectively registered. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
214. Transcriptome profiling reveals the association of multiple genes and pathways contributing to hormonal control in celery leaves.
- Author
-
Liu, Jiexia, Feng, Kai, Hou, Xilin, Li, Hui, Wang, Guanglong, Xu, Zhisheng, and Xiong, Aisheng
- Published
- 2019
- Full Text
- View/download PDF
215. Water transport, perception, and response in plants.
- Author
-
Scharwies, Johannes Daniel and Dinneny, José R.
- Subjects
RHIZOSPHERE ,PLANT cells & tissues ,SOIL science ,WATER supply ,PLANT physiology ,SOIL moisture - Abstract
Sufficient water availability in the environment is critical for plant survival. Perception of water by plants is necessary to balance water uptake and water loss and to control plant growth. Plant physiology and soil science research have contributed greatly to our understanding of how water moves through soil, is taken up by roots, and moves to leaves where it is lost to the atmosphere by transpiration. Water uptake from the soil is affected by soil texture itself and soil water content. Hydraulic resistances for water flow through soil can be a major limitation for plant water uptake. Changes in water supply and water loss affect water potential gradients inside plants. Likewise, growth creates water potential gradients. It is known that plants respond to changes in these gradients. Water flow and loss are controlled through stomata and regulation of hydraulic conductance via aquaporins. When water availability declines, water loss is limited through stomatal closure and by adjusting hydraulic conductance to maintain cell turgor. Plants also adapt to changes in water supply by growing their roots towards water and through refinements to their root system architecture. Mechanosensitive ion channels, aquaporins, proteins that sense the cell wall and cell membrane environment, and proteins that change conformation in response to osmotic or turgor changes could serve as putative sensors. Future research is required to better understand processes in the rhizosphere during soil drying and how plants respond to spatial differences in water availability. It remains to be investigated how changes in water availability and water loss affect different tissues and cells in plants and how these biophysical signals are translated into chemical signals that feed into signaling pathways like abscisic acid response or organ development. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
216. Sex-dependent effects of bisphenol A on type 1 diabetes development in non-obese diabetic (NOD) mice.
- Author
-
Xu, Joella, Guo, Tai L., Huang, Guannan, Nagy, Tamas, and Teng, Quincy
- Subjects
BISPHENOL A ,TYPE 1 diabetes ,OBESITY ,MICE ,IMMUNOREGULATION ,VANCOMYCIN ,GRAM-positive bacteria - Abstract
Type 1 diabetes (T1D) is an autoimmune disease caused by immune-mediated pancreatic β-cell destruction. The endocrine disrupting chemical bisphenol A (BPA) has widespread human exposure and can modulate immune function and the gut microbiome (GMB), which may contribute to the increasing T1D incidence worldwide. It was hypothesized that BPA had sex-dependent effects on T1D by modulating immune homeostasis and GMB. Adult female and male non-obese diabetic (NOD) mice were orally administered BPA at environmentally relevant doses (30 or 300 µg/kg). Antibiotic-treated adult NOD females were exposed to 0 or 30 µg/kg BPA. BPA accelerated T1D development in females, but delayed males from T1D. Consistently, females had a shift towards pro-inflammation (e.g., increased macrophages and Bacteroidetes), while males had increases in anti-inflammatory immune factors and a decrease in both anti- and pro-inflammatory GMB. Although bacteria altered during sub-acute BPA exposure differed from bacteria altered from chronic BPA exposure in both sexes, the GMB profile was consistently pro-inflammatory in females, while males had a general decrease of both anti- and pro-inflammatory gut microbes. However, treatment of females with the antibiotic vancomycin failed to prevent BPA-induced glucose intolerance, suggesting changes in Gram-positive bacteria were not a primary mechanism. In conclusion, BPA exposure was found to have sex dimorphic effects on T1D with detrimental effects in females, and immunomodulation was identified as the primary mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
217. Bisphenol A alteration of type 1 diabetes in non-obese diabetic (NOD) female mice is dependent on window of exposure.
- Author
-
Xu, Joella, Guo, Tai L., Huang, Guannan, and Nagy, Tamas
- Subjects
BISPHENOL A ,TYPE 1 diabetes ,OBESITY ,MICE ,IMMUNOREGULATION - Abstract
Type 1 diabetes (T1D) is an autoimmune disease in which pancreatic β-cell destruction can be mediated by dysbiosis, infiltration of pro-inflammatory immune cells, and cytokines/chemokines. Exposure to bisphenol A (BPA), an endocrine disruptor (ED), can lead to aberrant immunity and gut microbiota. We determined whether BPA had age-dependent effects on T1D by modulating immune homeostasis following various windows of exposure in non-obese diabetic (NOD) mice. Juvenile NOD females were orally exposed to 0 or 30 µg BPA/kg BW from postnatal day (PND) 28 to PND56. Adult NOD females were exposed to 0 or 300 µg BPA/kg BW. Female and male NOD offspring were exposed to 0 or 300 µg BPA/kg BW perinatally from gestation day 5 to PND28 by dosing the dams. It was found that BPA increased T1D risk in juvenile females with gut microbiota shifted towards pro-inflammation (e.g. increased Jeotgalicoccus). In agreement with our previous study, adult females had a trend of increased T1D and a general increase in immune responses. However, female offspring had a reduced T1D development. Consistently, female offspring had a shift towards anti-inflammation (e.g. decreased pro-inflammatory F4/80
+ Gr1+ cells). In contrast, BPA had minimal effects on immunity and T1D in male offspring. Thus, it was concluded that BPA had age- and sex-dependent effects on T1D with the alteration of gut microbiota and inflammation being the primary mechanisms for T1D exacerbation in juvenile exposure and decreases of inflammation being responsible for attenuated T1D in perinatally exposed females. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
218. Nitrogen increases drought tolerance in maize seedlings.
- Author
-
Song, Yushuang, Li, Jinlu, Liu, Mingli, Meng, Zhe, Liu, Kaichang, and Sui, Na
- Subjects
DROUGHT tolerance of corn ,CORN seedlings ,NITROGEN ,PHOTOSYSTEMS ,PHOTOSYNTHETIC rates - Abstract
Drought and nitrogen availability are two important environmental factors that affect plant growth and the global distribution of plants. We examined the effect of nitrogen on PSII in the leaves of maize seedlings under drought stress using three nitrogen concentrations (0.5, 7.5 and 15 mM) and three levels of water availability (normal conditions, mild drought and severe drought). Shoot fresh and dry weights and root fresh weight decreased with increasing drought conditions. In maize leaves subjected to drought stress, the chlorophyll a (Chl a) and chlorophyll b (Chl b) contents, net photosynthetic rate, transpiration rate, stomatal conductance, maximum chemical efficiency (F
v / Fm ), and photochemical efficiency of PSII (ΦPSII) were significantly reduced. Moderate nitrogen supply relieved the drought stress and enhanced the photosynthetic capacity. Malondialdehyde, H2 O2 and O2 −• accumulated in maize leaves under drought stress. Superoxide dismutase and ascorbate peroxidase activities increased in maize leaves under mild drought stress, but were significantly reduced under severe drought stress. The NO3 − content and nitrate reductase (NR) activity of maize leaves were significantly reduced under drought stress, while moderate nitrogen supply promoted the accumulation of NO3 − and an increase in the nitrate reductase activity. The abscisic acid content increased significantly; this increase was positively correlated with the nitrogen concentration under drought stress. Together, these results indicate that moderate nitrogen supply increases plant resistance to drought stress, while high or low nitrogen concentrations increase the sensitivity of maize to drought stress. These findings are important for guiding the agricultural use of nitrogen fertilisers. Drought and nitrogen availability are two important environmental factors that affect plant growth and global distribution of plants. We examined the effect of nitrogen on physiological characters of maize seedlings under drought stress and find that moderate nitrogen supply increases plant resistance to drought stress. These findings are important for guiding the agricultural use of nitrogen fertilisers. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
219. Interventions to Address Environmental Metabolism-Disrupting Chemicals: Changing the Narrative to Empower Action to Restore Metabolic Health.
- Author
-
Sargis, Robert M., Heindel, Jerrold J., and Padmanabhan, Vasantha
- Subjects
METABOLISM ,BIOCHEMISTRY ,METABOLOMICS ,BIOSYNTHESIS ,METABOLIC regulation - Abstract
Metabolic disease rates have increased dramatically over the last four decades. Classic understanding of metabolic physiology has attributed these global trends to decreased physical activity and caloric excess; however, these traditional risk factors insufficiently explain the magnitude and rapidity of metabolic health deterioration. Recently, the novel contribution of environmental metabolism-disrupting chemicals (MDCs) to various metabolic diseases (including obesity, diabetes, and non-alcoholic fatty liver disease) is becoming recognized. As this burgeoning body of evidence has matured, various organic and inorganic pollutants of human and natural origin have emerged as metabolic disease risk factors based on population-level and experimental data. Recognition of these heretofore underappreciated metabolic stressors now mandates that efforts to mitigate the devastating consequences of metabolic disease include dedicated efforts to address environmental drivers of disease risk; however, there have not been adequate recommendations to reduce exposures or to mitigate the effects of exposures on disease outcomes. To address this knowledge gap and advance the clinical translation of MDC science, herein discussed are behaviors that increase exposures to MDCs, interventional studies to reduce those exposures, and small-scale clinical trials to reduce the body burden of MDCs. Also, we discuss evidence from cell-based and animal studies that provide insights into MDC mechanisms of action, the influence of modifiable dietary factors on MDC toxicity, and factors that modulate MDC transplacental carriage as well as their impact on metabolic homeostasis. A particular emphasis of this discussion is on critical developmental windows during which short-term MDC exposure can elicit long-term disruptions in metabolic health with potential inter- and transgenerational effects. While data gaps remain and further studies are needed, the current state of evidence regarding interventions to address MDC exposures illuminates approaches to address environmental drivers of metabolic disease risk. It is now incumbent on clinicians and public health agencies to incorporate this knowledge into comprehensive strategies to address the metabolic disease pandemic. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
220. Sex-Specific Gene Expression in the Mouse Nucleus Accumbens Before and After Cocaine Exposure.
- Author
-
LaRese, Taylor P, Rheaume, Bruce A, Abraham, Ron, Eipper, Betty A, and Mains, Richard E
- Subjects
GENE expression ,NUCLEUS accumbens ,COCAINE - Abstract
The nucleus accumbens plays a major role in the response of mammals to cocaine. In animal models and human studies, the addictive effects of cocaine and relapse probability have been shown to be greater in females. Sex-specific differential expression of key transcripts at baseline and after prolonged withdrawal could underlie these differences. To distinguish between these possibilities, gene expression was analyzed in four groups of mice (cycling females, ovariectomized females treated with estradiol or placebo, and males) 28 days after they had received seven daily injections of saline or cocaine. As expected, sensitization to the locomotor effects of cocaine was most pronounced in the ovariectomized mice receiving estradiol, was greater in cycling females than in males, and failed to occur in ovariectomized/placebo mice. After the 28-day withdrawal period, RNA prepared from the nucleus accumbens of the individual cocaine- or saline-injected mice was subjected to RNA sequencing analysis. Baseline expression of 3% of the nucleus accumbens transcripts differed in the cycling female mice compared with the male mice. Expression of a similar number of transcripts was altered by ovariectomy or was responsive to estradiol treatment. Nucleus accumbens transcripts differentially expressed in cycling female mice withdrawn from cocaine exhibited substantial overlap with those differentially expressed in cocaine-withdrawn male mice. A small set of transcripts were similarly affected by cocaine in the placebo- or estradiol-treated ovariectomized mice. Sex and hormonal status have profound effects on RNA expression in the nucleus accumbens of naive mice. Prolonged withdrawal from cocaine alters the expression of a much smaller number of common and sex hormone-specific transcripts. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
221. Hydrogen peroxide plays an important role in PERK4-mediated abscisic acid-regulated root growth in Arabidopsis.
- Author
-
Ma, Xiaonan, Zhang, Xiaoran, Yang, Ling, Tang, Mengmeng, Wang, Kai, Wang, Li, Bai, Ling, and Song, Chunpeng
- Subjects
HYDROGEN peroxide ,ABSCISIC acid ,ROOT growth ,ARABIDOPSIS ,REACTIVE oxygen species - Abstract
Abscisic acid (ABA) is a crucial factor that affects primary root tip growth in plants. Previous research suggests that reactive oxygen species (ROS), especially hydrogen peroxide, are important regulators of ABA signalling in root growth of Arabidopsis. PROLINE - RICH EXTENSIN - LIKE RECEPTOR KINASE 4 (PERK4) plays an important role in ABA responses. Arabidopsis perk4 mutants display attenuated sensitivity to ABA, especially in primary root growth. To gain insights into the mechanism(s) of PERK4-associated ABA inhibition of root growth, in this study we investigated the involvement of ROS in this process. Normal ROS accumulation in the primary root in response to exogenous ABA treatment was not observed in perk4 mutants. PERK4 deficiency prohibits ABA-induced expression of RESPIRATORY BURST OXIDASE HOMOLOGUE (RBOH) genes, therefore the perk4 - 1 mutant showed decreased production of ROS in the root. The perk4 - 1 / rbohc double mutant displayed the same phenotype as the perk4 and rbohc single mutants in response to exogenous ABA treatment. The results suggest that PERK4-stimulated ROS accumulation during ABA-regulated primary root growth may be mediated by RBOHC. Reactive oxygen species (ROS) are important regulators of ABA signalling in root growth. This work aimed to explore the mechanisms of PERK4-associated ABA inhibition of root growth. Our results provided new perspectives that enhance our understanding of the process, and provided a foundation for elucidation of the molecular mechanisms of PERK4-mediated ABA-regulated primary root growth. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
222. Sexual dimorphism in brain transcriptomes of Amami spiny rats (Tokudaia osimensis): a rodent species where males lack the Y chromosome.
- Author
-
Ortega, Madison T., Bivens, Nathan J., Jogahara, Takamichi, Kuroiwa, Asato, Givan, Scott A., and Rosenfeld, Cheryl S.
- Subjects
STEROID hormones ,BRAIN ,TESTOSTERONE ,ESTROGEN ,AROMATASE - Abstract
Background: Brain sexual differentiation is sculpted by precise coordination of steroid hormones during development. Programming of several brain regions in males depends upon aromatase conversion of testosterone to estrogen. However, it is not clear the direct contribution that Y chromosome associated genes, especially sex-determining region Y (Sry), might exert on brain sexual differentiation in therian mammals. Two species of spiny rats: Amami spiny rat (Tokudaia osimensis) and Tokunoshima spiny rat (T. tokunoshimensis) lack a Y chromosome/Sry, and these individuals possess an XO chromosome system in both sexes. Both Tokudaia species are highly endangered. To assess the neural transcriptome profile in male and female Amami spiny rats, RNA was isolated from brain samples of adult male and female spiny rats that had died accidentally and used for RNAseq analyses. Results: RNAseq analyses confirmed that several genes and individual transcripts were differentially expressed between males and females. In males, seminal vesicle secretory protein 5 (Svs5) and cytochrome P450 1B1 (Cyp1b1) genes were significantly elevated compared to females, whereas serine (or cysteine) peptidase inhibitor, clade A, member 3 N (Serpina3n) was upregulated in females. Many individual transcripts elevated in males included those encoding for zinc finger proteins, e.g. zinc finger protein X-linked (Zfx). Conclusions: This method successfully identified several genes and transcripts that showed expression differences in the brain of adult male and female Amami spiny rat. The functional significance of these findings, especially differential expression of transcripts encoding zinc finger proteins, in this unusual rodent species remains to be determined. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
223. Microbial treatment: the potential application for Parkinson's disease.
- Author
-
Fang, Xin
- Subjects
FECAL microbiota transplantation ,PARKINSON'S disease ,PARKINSON'S disease treatment ,ANIMALS ,PROBIOTICS ,TREATMENT effectiveness - Abstract
Alterations in the composition of the intestinal flora are associated with the pathophysiology of Parkinson's disease (PD). More importantly, the possible cause-effect links between gut flora and PD pathogenesis have been identified using PD animal models. Recent studies have found that probiotics improve the symptoms associated with constipation in PD patients. In addition, fecal microbiota transplantation (FMT) was recently shown to provide a protective effect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in mice. Effective microbial therapy for PD includes probiotics and FMT. Therefore, microbial therapy may be a useful and novel approach for treatment of PD. In this review, I discuss the use of microbial treatment in PD. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
224. Abscisic acid accumulation modulates auxin transport in the root tip to enhance proton secretion for maintaining root growth under moderate water stress.
- Author
-
Xu W, Jia L, Shi W, Liang J, Zhou F, Li Q, and Zhang J
- Subjects
- Abscisic Acid pharmacology, Adaptation, Physiological, Arabidopsis drug effects, Arabidopsis growth & development, Biological Transport, Cell Membrane enzymology, Dehydration metabolism, Enzyme Activation, Enzyme Assays, Hydroponics methods, Indoleacetic Acids analysis, Oryza drug effects, Oryza growth & development, Plant Roots drug effects, Plant Roots metabolism, Polyethylene Glycols pharmacology, Proton-Translocating ATPases metabolism, Protons, Stress, Physiological, Water metabolism, Abscisic Acid metabolism, Arabidopsis metabolism, Indoleacetic Acids metabolism, Oryza metabolism, Plant Roots growth & development
- Abstract
Maintenance of root growth is essential for plant adaptation to soil drying. Here, we tested the hypothesis that auxin transport is involved in mediating ABA's modulation by activating proton secretion in the root tip to maintain root growth under moderate water stress. Rice and Arabidopsis plants were raised under a hydroponic system and subjected to moderate water stress (-0.47 MPa) with polyethylene glycol (PEG). ABA accumulation, auxin transport and plasma membrane H(+)-ATPase activity at the root tip were monitored in addition to the primary root elongation and root hair density. We found that moderate water stress increases ABA accumulation and auxin transport in the root apex. Additionally, ABA modulation is involved in the regulation of auxin transport in the root tip. The transported auxin activates the plasma membrane H(+)-ATPase to release more protons along the root tip in its adaption to moderate water stress. The proton secretion in the root tip is essential in maintaining or promoting primary root elongation and root hair development under moderate water stress. These results suggest that ABA accumulation modulates auxin transport in the root tip, which enhances proton secretion for maintaining root growth under moderate water stress., (© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.)
- Published
- 2013
- Full Text
- View/download PDF
225. Physiological and molecular analysis of polyethylene glycol-induced reduction of aluminium accumulation in the root tips of common bean (Phaseolus vulgaris).
- Author
-
Yang ZB, Eticha D, Rotter B, Rao IM, and Horst WJ
- Subjects
- Cell Wall drug effects, Cell Wall genetics, Databases, Genetic, Expressed Sequence Tags, Gene Expression Profiling, Gene Expression Regulation, Plant drug effects, Gene Library, Genes, Plant genetics, Meristem genetics, Meristem growth & development, Models, Biological, Osmosis drug effects, Phaseolus drug effects, Plant Proteins genetics, Plant Proteins metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Reproducibility of Results, Aluminum metabolism, Meristem drug effects, Meristem metabolism, Phaseolus genetics, Phaseolus physiology, Polyethylene Glycols pharmacology
- Abstract
• Aluminium (Al) toxicity and drought are two major stress factors limiting common bean (Phaseolus vulgaris) production on tropical acid soils. Polyethylene glycol (PEG) treatment reduces Al uptake and Al toxicity. • The effect of PEG 6000-induced osmotic stress on the expression of genes was studied using SuperSAGE combined with next-generation sequencing and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for selected genes. • Less Al stress in PEG-treated roots was confirmed by decreased Al-induced up-regulation of MATE and ACCO genes. The withdrawal of PEG from the Al treatment solution restored the Al accumulation and reversed the expression of MATE and ACCO genes to the level of the treatment with Al alone. Using SuperSAGE, we identified 611 up- and 728 down-regulated genes in PEG-treated root tips, and the results were confirmed by qRT-PCR using 46 differentially expressed genes. Among the 12 genes studied in more detail, XTHa and BEG (down-regulated by PEG) and HRGP, bZIP, MYB and P5CS (up-regulated by PEG) recovered completely within 2 h after removal of PEG stress. • The results suggest that genes related to cell wall assembly and modification, such as XTHs, BEG and HRGP, play important roles in the PEG-induced decrease in cell wall porosity, leading to reduced Al accumulation in root tips., (© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.)
- Published
- 2011
- Full Text
- View/download PDF
226. Mechanism of Auxin Mediated Stress Signaling in Plants.
- Published
- 2017
- Full Text
- View/download PDF
227. The emergence of preclinical studies on the role of the microbiome in lung development and experimental animal models of bronchopulmonary dysplasia.
- Author
-
Casado, Francisco and Morty, Rory E.
- Published
- 2020
- Full Text
- View/download PDF
228. PYL8 mediates ABA perception in the root through non-cell-autonomous and ligand-stabilization-based mechanisms.
- Author
-
Belda-Palazon, Borja, Gonzalez-Garcia, Mary-Paz, Lozano-Juste, Jorge, Coego, Alberto, Antoni, Regina, Julian, Jose, Peirats-Llobet, Marta, Rodriguez, Lesia, Berbel, Ana, Dietrich, Daniela, Fernandez, Maria A., Madueño, Francisco, Bennett, Malcolm J., and Rodriguez, Pedro L.
- Subjects
ABSCISIC acid ,PLANT hormones ,BIOSENSORS ,PLANT roots ,PLANT cells & tissues ,ROOT growth - Abstract
The phytohormone abscisic acid (ABA) plays a key role regulating root growth, root system architecture, and root adaptive responses, such as hydrotropism. The molecular and cellular mechanisms that regulate the action of core ABA signaling components in roots are not fully understood. ABA is perceived through receptors from the PYR/PYL/RCAR family and PP2C coreceptors. PYL8/RCAR3 plays a nonredundant role in regulating primary and lateral root growth. Here we demonstrate that ABA specifically stabilizes PYL8 compared with other ABA receptors and induces accumulation of PYL8 in root nuclei. This requires ABA perception by PYL8 and leads to diminished ubiquitination of PYL8 in roots. The ABA agonist quinabactin, which promotes root ABA signaling through dimeric receptors, fails to stabilize the monomeric receptor PYL8. Moreover, a PYL8 mutant unable to bind ABA and inhibit PP2C is not stabilized by the ligand, whereas a PYL8
5KR mutant is more stable than PYL8 at endogenous ABA concentrations. The PYL8 transcript was detected in the epidermis and stele of the root meristem; however, the PYL8 protein was also detected in adjacent tissues. Expression of PYL8 driven by tissue-specific promoters revealed movement to adjacent tissues. Hence both inter- and intracellular trafficking of PYL8 appears to occur in the root apical meristem. Our findings reveal a non-cell-autonomous mechanism for hormone receptors and help explain the nonredundant role of PYL8-mediated root ABA signaling. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
229. Abscisic acid and its metabolites are involved in drought tolerance in four native species of Patagonian semiarid shrublands (Argentina).
- Author
-
Cenzano, Ana M., Reginato, Mariana, Varela, M. Celeste, and Luna, M. Virginia
- Abstract
Drought is the main stress that affects growth of native species of Patagonian Monte. Physiological and biochemical traits with functional roles in adaptation to drought are still scarce in native species. The aim of this study was to evaluate changes in dry matter content and abscisic acid (ABA) and its metabolites (phaseic acid-PA, dihydrophaseic acid-DPA, ABA conjugated with glucose-ABA-GE) level in green leaves and fine roots of four native species during contrasting seasons regarding water availability. Results show that grasses had higher leaf dry matter content (LDMC) and root dry matter content (RDMC) than Lycium chilense shrub and LDMC decreased during autumn in Larrea divaricata. In green leaves, there was an interaction between species and seasons for ABA and PA contents. L. divaricata had high ABA content during spring and low ABA content during autumn; while L. chilense showed the opposite pattern. During spring, drought tolerant species had high PA content while drought avoidant species had low PA content, and during autumn these species showed the opposite pattern. ABA-GE content was highest in L. chilense green leaves. In fine roots, ABA content was highest in L. divaricata and during spring PA was higher in L. divaricata than P. ligularis and L. chilense. PA was the only metabolite that decreased in L. divaricata during autumn. Results showed that ABA homeostasis maintains the functioning of different life forms with different drought resistance strategies in Patagonia semiarid shrublands. In green leaves of the drought avoidant L. chilense shrub, the ABA conjugation pathway was active in both seasons. During spring, the most drought tolerant L. divaricata showed highest activation of ABA synthesis and ABA oxidation pathways. During autumn L. chilense showed highest activation of ABA synthesis and together with P. ligularis showed active the ABA oxidation pathway. The identification of physiological and biochemical traits with functional roles in adaptation to drought is still scarce for native species of arid regions, and this knowledge would be useful to planning the conservation of these ecosystems. Our findings show that abscisic acid metabolite profiling contributes to maintaining the functioning of grasses and shrubs belonging to different functional types (e.g. evergreen vs deciduous; drought tolerant vs drought avoidant) inhabiting natural drought conditions of Patagonian semiarid shrublands. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
230. Stochastic modelling of relative water permeability in vegetative soils with implications on stability of bioengineered slope.
- Author
-
Singh, Shivam Raj, Prakash, Atma, Hazra, Budhaditya, Sarmah, Ajit, Garg, Ankit, and Zhu, Hong-Hu
- Subjects
SOIL permeability measurement ,STOCHASTIC models ,GROUND vegetation cover ,SLOPE stability ,BIOENGINEERING ,PROBABILITY theory - Abstract
Vegetation is known to influence the hydrological state variables, suction ψ and volumetric water content (θw) of soil. In addition, vegetation induces heterogeneity in the soil porous structure and consequently the relative permeability (kr) of water under unsaturated conditions. The indirect method of utilising the soil water characteristic curve (SWCC) is commonly adopted for the determination of kr. In such cases, it is essential to address the stochastic behaviour of SWCC, in order to conduct a robust analysis on the kr of vegetative cover. The main aim of this study is to address the uncertainties associated with kr, using probabilistic analysis, for vegetative covers (i.e., grass and tree species) with bare cover as control treatment. We propose two approaches to accomplish the aforesaid objective. The univariate suction approach predicts the probability distribution functions of kr, on the basis of identified best probability distribution of suction. The bivariate suction and water content approach deals with the bivariate modelling of the water content and suction (SWCC), in order to capture the randomness in the permeability curves, due to presence of vegetation. For this purpose, the dependence structure of ψ and θw is established via copula theory, and the kr curves are predicted with respect to varying levels of ψ-θw correlation. The results showed that the kr of vegetative covers is substantially lower than that in bare covers. The reduction in kr with drying is more in tree cover than grassed cover, since tree roots induce higher levels of suction. Moreover, the air entry value of the soil depends on the magnitude of ψ-θw correlation, which in turn, is influenced by the type of vegetation in the soil. kr is found to be highly uncertain in the desaturation zone of the relative permeability curve. The stochastic behaviour of kr is found to be most significant in tree covers. Finally, a simplified case study is also presented in order to demonstrate the impact of the uncertainty in kr, on the stability of vegetates slopes. With an increment in the parameter α, factor of safety (FS) is found to decrease. The trend of FS is reverse of this with parameter n. Overall FS is found to vary around 4-5%, for both bare and vegetative slopes. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
231. High-throughput sequencing of small RNAs revealed the diversified cold-responsive pathways during cold stress in the wild banana (Musa itinerans).
- Author
-
Liu, Weihua, Cheng, Chunzhen, Chen, Fanglan, Ni, Shanshan, Lin, Yuling, and Lai, Zhongxiong
- Subjects
EFFECT of cold on plants ,BANANAS ,MICRORNA ,PHYSIOLOGICAL effects of cold temperatures ,ABIOTIC stress ,RNA sequencing - Abstract
Background: Cold stress is one of the most severe abiotic stresses affecting the banana production. Although some miRNAs have been identified, little is known about the role of miRNAs in response to cold stress in banana, and up to date, there is no report about the role of miRNAs in the response to cold stress in the plants of the cultivated or wild bananas. Result: Here, a cold-resistant line wild banana (Musa itinerans) from China was used to profile the cold-responsive miRNAs by RNA-seq during cold stress. Totally, 265 known mature miRNAs and 41 novel miRNAs were obtained. Cluster analysis of differentially expressed (DE) miRNAs indicated that some miRNAs were specific for chilling or 0 °C treated responses, and most of them were reported to be cold-responsive; however, some were seldom reported to be cold-responsive in response to cold stress, e.g., miR395, miR408, miR172, suggesting that they maybe play key roles in response to cold stress. The GO and KEGG pathway enrichment analysis of DE miRNAs targets indicated that there existed diversified cold-responsive pathways, and miR172 was found likely to play a central coordinating role in response to cold stress, especially in the regulation of CK2 and the circadian rhythm. Finally, qPCR assays indicated the related targets were negatively regulated by the tested DE miRNAs during cold stress in the wild banana. Conclusions: In this study, the profiling of miRNAs by RNA-seq in response to cold stress in the plants of the wild banana (Musa itinerans) was reported for the first time. The results showed that there existed diversified cold-responsive pathways, which provided insight into the roles of miRNAs during cold stress, and would be helpful for alleviating cold stress and cold-resistant breeding in bananas. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
232. Phytohormones enhanced drought tolerance in plants: a coping strategy.
- Author
-
Ullah, Abid, Manghwar, Hakim, Shaban, Muhammad, Khan, Aamir Hamid, Akbar, Adnan, Ali, Usman, Ali, Ehsan, and Fahad, Shah
- Subjects
PLANT hormones ,DROUGHTS ,ABSCISIC acid ,CYTOKININS ,ZEATIN - Abstract
Drought stress is a severe environmental constraint among the emerging problems. Plants are highly vulnerable to drought stress and a severe decrease in yield was recorded in the last few decades. So, it is highly desirable to understand the mechanism of drought tolerance in plants and consequently enhance the tolerance against drought stress. Phytohormones are known to play vital roles in regulating various phenomenons in plants to acclimatize to varying drought environment. Abscisic acid (ABA) is considered the main hormone which intensifies drought tolerance in plants through various morpho-physiological and molecular processes including stomata regulation, root development, and initiation of ABA-dependent pathway. In addition, jasmonic acid (JA), salicylic acid (SA) ethylene (ET), auxins (IAA), gibberellins (GAs), cytokinins (CKs), and brassinosteroids (BRs) are also very important phytohormones to congregate the challenges of drought stress. However, these hormones are usually cross talk with each other to increase the survival of plants in drought conditions. On the other hand, the transgenic approach is currently the most accepted technique to engineer the genes responsible for the synthesis of phytohormones in drought stress response. Our present review highlights the regulatory circuits of phytohormones in drought tolerance mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
233. Effects of water decontamination methods and bedding material on the gut microbiota.
- Author
-
Bidot, Willie A., Ericsson, Aaron C., and Franklin, Craig L.
- Subjects
WATER pollution ,GUT microbiome ,PUBLIC health ,COLON cancer treatment ,HYDROCHLORIC acid - Abstract
Rodent models are invaluable to understanding health and disease in many areas of biomedical research. Unfortunately, many models suffer from lack of phenotype reproducibility. Our laboratory has shown that differences in gut microbiota (GM) can modulate phenotypes of models of colon cancer and inflammatory bowel disease. We and others have also shown that a number of factors associated with rodent research, including vendor, cage system, and bedding can alter GM. The objective of this study was to expand these studies to examine the effect of additional bedding materials and methods of water decontamination on GM diversity and composition. To this end, Crl:CD1 (ICR) mice were housed on corn cob or compressed paper chip bedding and provided water that was decontaminated by four different methods: autoclaving with reverse osmosis, autoclaving with hydrochloric acid, autoclaving with sulfuric acid, and autoclaving alone. Feces was collected at day 0, and at day 28 (endpoint), fecal and cecal samples were collected. DNA was extracted from samples, amplified by PCR using conserved bacterial primer sets and subjected to next generation sequencing. Sequence data were analyzed using Qiime and groups were compared using principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA). Two factor PERMANOVA of cecal GM data revealed significant changes when comparing bedding and water decontamination methods, while no significant effects were noted in the fecal GM data. Subsequent PERMANOVA and PCoA of cecal data revealed that several combinations of bedding and water decontamination methods resulted in differing GM, highlighting the complexity by which environmental factors interact to modulate GM. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
234. Quantitative dissection of variations in root growth rate: a matter of cell proliferation or of cell expansion?
- Author
-
Youssef, Chvan, Bizet, François, Bastien, Renaud, Legland, David, Bogeat-Triboulot, Marie-Béatrice, and Hummel, Irène
- Subjects
ROOT growth ,CELL proliferation ,POLYETHYLENE glycol ,PLANT growth ,PLANT variation ,PLANTS - Abstract
Plant organ growth results from cell production and cell expansion. Deciphering the contribution of each of these processes to growth rate is an important issue in developmental biology. Here, we investigated the cellular processes governing root elongation rate, considering two sources of variation: genotype and disturbance by chemicals (NaCl, polyethylene glycol, H
2 O2 , abscisic acid). Exploiting the adventitious rooting capacity of the Populus genus, and using time-lapse imaging under infrared-light, particle image velocimetry, histological analysis, and kinematics, we quantified the cellular processes involved in root growth variation, and analysed the covariation patterns between growth parameters. The rate of cell production by the root apical meristem and the number of dividing cells were estimated in vivo without destructive measurement. We found that the rate of cell division contributed more to the variation in cell production rate than the number of dividing cells. Regardless of the source of variation, the length of the elongation zone was the best proxy for growth rate, summarizing rates of cell production and cell elongation into a single parameter. Our results demonstrate that cell production rate is the main driver of growth rate, whereas elemental elongation rate is a key driver of short-term growth adjustments. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
235. Physiological and biochemical analyses reveal drought tolerance in cool-season tall fescue (Festuca arundinacea) turf grass with the application of melatonin.
- Author
-
Alam, Mohammad Nur, Wang, Yanping, and Chan, Zhulong
- Subjects
TALL fescue ,DROUGHT tolerance ,MELATONIN - Abstract
Tall fescue (Festuca arundinacea Schreb.) is a widely used, cool-season turf grass and is relatively sensitive to water stress. Melatonin has been reported to improve abiotic stress tolerance in many plants. In this study, we demonstrated that, although shoot height and fresh weight of tall fescue seedlings were significantly reduced by drought stress, they were increased by melatonin pre-treatment compared with control plants. Chemical analyses showed that tall fescue seedlings pre-treated with melatonin exhibited decreased levels of reactive oxygen species, electrolyte leakage and malondialdehyde, but higher levels of antioxidant enzyme activities (catalase, and peroxidase) and total chlorophyll content, compared with untreated seedlings. Leaf water loss was also partially mitigated and leaf water content increased by melatonin application, resulting in improved plant growth under drought stress. Moreover, root growth of tall fescue seedlings was promoted by melatonin under osmotic stress. The results show that drought tolerance was improved in cool-season tall fescue by application of exogenous melatonin. Therefore, melatonin may potentially be used as a protectant for plants against the deleterious effects of drought or water-deficit stress. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
236. Maturation of Atriplex halimus L. leaves involves changes in the molecular regulation of stomatal conductance under high evaporative demand and high but not low soil water content.
- Author
-
Nada, Reham M., Khedr, Abdel Hamid A., Serag, Mamdouh S., El-Qashlan, Nesma R., and Abogadallah, Gaber M.
- Subjects
ATRIPLEX ,STOMATA ,SOIL moisture ,WATER supply ,PHOTOSYNTHETIC rates ,GENE expression ,PHOTOSYNTHESIS - Abstract
Main conclusion: Under high water availability, the maximum gas exchange was observed at noon in the expanding and expanded leaves. The expanded leaves showed lower gas exchange capacity due to the regulation of stomatal-movement genes.Under well-watered condition, stomatal conductance (g
s ) and photosynthetic rate (A) of expanding and expanded leaves of Atriplex halimus peaked at noon despite the midday decline in the leaf relative water content, suggesting deviation from typical isohydric behaviour. However, the expanding leaves had higher gs and A than the expanded ones. When light intensity was temporarily increased, A and gs were enhanced in both types of leaves though to a higher level in the expanding leaves. In well-watered expanded leaves: (1) A was mainly dependent on gs rather than photosynthetic capacity; gs was controlled by internal factors, thereby limiting water loss via transpiration (E); (2) the accumulation of total soluble sugars (TSS) along with increased Rubisco protein could be a subsidiary factor limiting A; (3) TSS and ABA seem to act in co-ordination to up-regulate ABA-dependent genes controlling gs and (4) the significant induction of DREBs suggests a role in maintaining high relative water content in these leaves compared to the expanding ones. In expanding leaves of well-watered plants, high A along with Rubisco down-regulation and elevated TSS suggests that A was regulated by signals coordinating carbon and nitrogen balance and the elevated ABA could be involved in regulating the hydraulic activity to enhance cell expansion and facilitate leaf growth. Both expanded and expanding leaves behaved in typical isohydric manner under water stress, which did not involve the accumulation of ABA suggesting that stomatal closure was primarily stimulated by hydraulic rather than chemical signals. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
237. Engineered commensal bacteria prevent systemic inflammation-induced memory impairment and amyloidogenesis via producing GLP-1.
- Author
-
Chen, Tingtao, Tian, Puyuan, Huang, Zhixiang, Zhao, Xiaoxiao, Wang, Huan, Xia, Chaofei, Wang, Le, and Wei, Hua
- Subjects
GLUCAGON-like peptide 1 ,CENTRAL nervous system ,MEMORY disorders ,PHOSPHORYLATION ,LABORATORY mice ,THERAPEUTICS - Abstract
The anti-obesity drug GLP-1 has been proven to have an impact on central nervous system, while its extremely short half-life greatly limited its use. In this study, our group constructed two engineering strains MG1363-pMG36e-GLP-1 and VNP20009-pLIVE-GLP-1 to continuously express GLP-1, and supplementation of these strains, especially MG1363-pMG36e-GLP-1, had significantly restored the spatial learning and memory impairment of mice caused by LPS (p < 0.05), suppressed glia activation and Aβ accumulation, and downregulated inflammatory expressions of COX-2, TLR-4, TNF-a, and IL-1β. In addition, MG1363-pMG36e-GLP-1 had significantly blocked the translocation of NF-κB signal and inhibited the phosphorylation of redox-sensitive cytoplasmic signalings of MAPKs and PI3K/AKT. These data suggest that MG1363-pMG36e-GLP-1 could be used as a safe and effective nonabsorbed oral treatment for neuroinflammation-related diseases such as Alzheimer’s disease (AD). [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
238. Overexpression of the rice gene OsSIZ1 in Arabidopsis improves drought-, heat-, and salt-tolerance simultaneously.
- Author
-
Mishra, Neelam, Srivastava, Anurag P., Esmaeili, Nardana, Hu, Wenjun, and Shen, Guoxin
- Subjects
UBIQUITIN ,GENETIC overexpression ,RICE genetics ,ARABIDOPSIS ,PLANT growth - Abstract
Sumoylation is one of the post translational modifications, which affects cellular processes in plants through conjugation of small ubiquitin like modifier (SUMO) to target substrate proteins. Response to various abiotic environmental stresses is one of the major cellular functions regulated by SUMO conjugation. SIZ1 is a SUMO E3 ligase, facilitating a vital step in the sumoylation pathway. In this report, it is demonstrated that over-expression of the rice gene OsSIZ1 in Arabidopsis leads to increased tolerance to multiple abiotic stresses. For example, OsSIZ1-overexpressing plants exhibited enhanced tolerance to salt, drought, and heat stresses, and generated greater seed yields under a variety of stress conditions. Furthermore, OsSIZ1-overexpressing plants were able to exclude sodium ions more efficiently when grown in saline soils and accumulate higher potassium ions as compared to wild-type plants. Further analysis revealed that OsSIZ1-overexpressing plants expressed higher transcript levels of P5CS, a gene involved in the biosynthesis of proline, under both salt and drought stress conditions. Therefore, proline here is acting as an osmoprotectant to alleviate damages caused by drought and salt stresses. These results demonstrate that the rice gene OsSIZ1 has a great potential to be used for improving crop’s tolerance to several abiotic stresses. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
239. Differential response to heat stress in outer and inner onion bulb scales.
- Author
-
Galsurker, Ortal, Doron-Faigenboim, Adi, Teper-Bamnolker, Paula, Daus, Avinoam, Lers, Amnon, and Eshel, Dani
- Subjects
ONIONS ,PHYSIOLOGICAL effects of heat ,ENZYMATIC browning ,PHYSIOLOGICAL oxidation ,TRANSCRIPTOMES - Abstract
The formation of brown protective skin in onion bulbs can be induced by rapid post-harvest heat treatment. Onions that are peeled to different depths and are exposed to heat stress show that only the outer scales form the dry brown skin, whereas the inner scales maintain high water content and do not change color. Our study demonstrates that browning of the outer scale during heat treatment is due to an enzymatic process that is associated with high levels of oxidation components, such as peroxidase and quercetin glucoside. De novo transcriptome analysis revealed differential molecular responses of the outer and inner scales to heat stress. Genes involved in lipid metabolism, oxidation pathways, and cell-wall modification were highly expressed in the outer scale during heating. Defense response-related genes such as those encoding heat-shock proteins, antioxidative stress defense, or production of osmoprotectant metabolites were mostly induced in the inner scale in response to heat exposure. These transcriptomic data led to a conceptual model that suggests sequential processes for the development of browning and desiccation of the outer scale versus processes associated with defense response and heat tolerance in the inner scales. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
240. Characterization of PP2A-A3 mRNA expression and growth patterns in Arabidopsis thaliana under drought stress and abscisic acid.
- Author
-
Razavizadeh, Roya, Shojaie, Behrokh, and Komatsu, Setsuko
- Abstract
Phosphoprotein phosphatase 2A (PP2A) plays a crucial role in cellular processes via reversible dephosphorylation of proteins. The activity of this enzyme depends on its subunits. There is little information about mRNA expression of each subunit and the relationship between these gene expressions and the growth patterns under stress conditions and hormones. Here, mRNA expression of subunit A3 of PP2A and its relationship with growth patterns under different levels of drought stress and abscisic acid (ABA) concentration were analyzed in Arabidopsis thaliana. The mRNA expression profiles showed different levels of the up- and down-regulation of PP2AA3 in roots and shoots of A. thaliana under drought conditions and ABA treatments. The results demonstrated that the regulation of PP2AA3 expression under the mentioned conditions could indirectly modulate growth patterns such that seedlings grown under severe drought stress and those grown under 4 µM ABA had the maximum number of lateral roots and the shortest primary roots. In contrast, the minimum number of lateral roots and the longest primary roots were observed under mild drought stress and 0.5 µM ABA. Differences in PP2AA3 mRNA expression showed that mechanisms involved in the regulation of this gene under drought conditions would probably be different from those that regulate the PP2AA3 expression under ABA. Co-expression of PP2AA3 with each of PIN1-4,7 (PP2A activity targets) depends on the organ type and different levels of drought stress and ABA concentration. Furthermore, fluctuations in the PP2AA3 expression proved that this gene cannot be suitable as a reference gene although PP2AA3 is widely used as a reference gene. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
241. Gene expression and DNA methylation changes in the hypothalamus and hippocampus of adult rats developmentally exposed to bisphenol A or ethinyl estradiol: a CLARITY-BPA consortium study.
- Author
-
Cheong, Ana, Johnson, Sarah A., Howald, Emily C., Ellersieck, Mark R., Camacho, Luísa, Lewis, Sherry M., Vanlandingham, Michelle M., Ying, Jun, Ho, Shuk-Mei, and Rosenfeld, Cheryl S.
- Abstract
Bisphenol A (BPA), an endocrine disrupting chemical (EDC), is a ubiquitous pollutant. As part of the Consortium Linking Academic and Regulatory Insights on BPA Toxicity (CLARITY-BPA), we sought to determine whether exposure of Sprague-Dawley rats to 2,500 μg/kg/day BPA (BPA) or 0.5 μg/kg/day ethinyl estradiol (EE) from gestational day 6 through postnatal day 21 induces behavior-relevant gene expression and DNA methylation changes in hippocampus and hypothalamus at adulthood. RNA and DNA were isolated from both regions. Expression of ten genes (Dnmt1, Dnmt3a, Dnmt3b, Esr1, Esr2, Avp, Ar, Oxt, Otr, and Bdnf) presumably altered by early-life BPA/EE exposure was examined. Three genes (Bdnf, Dnmt3b, and Esr1) were studied for DNA methylation changes in their putative 5ʹ promoter regions. Molecular changes in hippocampus were correlated to prior Barnes maze performance, including sniffing correct holes, distance traveled, and velocity. Exposure to BPA and/or EE disrupted patterns of sexually dimorphic gene expression/promoter DNA methylation observed in hippocampus and hypothalamus of controls. In the hippocampus of female offspring, BPA exposure resulted in hypermethylation of the putative 5ʹ promoter region of Bdnf, while EE exposure induced hypomethylation. Bdnf methylation was weakly associated with Bdnf expression in hippocampi of female rats. Hippocampal Bdnf expression in females showed a weak negative association with sniffing correct hole in Barnes maze. Hippocampal expression of Avp, Esr2, Oxt, and Otr was strongly associated with velocity of control rats in Barnes maze. Findings suggest BPA exposure induced non-EE-like gene expression and epigenetic changes in adult rat hippocampi, a region involved in spatial navigation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
242. Multigenerational effects of bisphenol A or ethinyl estradiol exposure on F2 California mice (Peromyscus californicus) pup vocalizations.
- Author
-
Johnson, Sarah A., Farrington, Michelle J., Murphy, Claire R., Caldo, Paul D., McAllister, Leif A., Kaur, Sarabjit, Chun, Catherine, Ortega, Madison T., Marshall, Brittney L., Hoffmann, Frauke, Ellersieck, Mark R., Schenk, A. Katrin, and Rosenfeld, Cheryl S.
- Subjects
PEROMYSCUS californicus ,PHYSIOLOGICAL effects of chemicals ,BISPHENOL A ,ETHINYL estradiol ,VOCALIZATION in mammals ,ENDOCRINE disruptors ,MAMMAL development - Abstract
Rodent pups use vocalizations to communicate with one or both parents in biparental species, such as California mice (Peromyscus californicus). Previous studies have shown California mice developmentally exposed to endocrine disrupting chemicals, bisphenol A (BPA) or ethinyl estradiol (EE), demonstrate later compromised parental behaviors. Reductions in F
1 parental behaviors might also be due to decreased emissions of F2 pup vocalizations. Thus, vocalizations of F2 male and female California mice pups born to F1 parents developmentally exposed to BPA, EE, or controls were examined. Postnatal days (PND) 2–4 were considered early postnatal period, PND 7 and 14 were defined as mid-postnatal period, and PND 21 and 28 were classified as late postnatal period. EE pups showed increased latency to emit the first syllable compared to controls. BPA female pups had decreased syllable duration compared to control and EE female pups during the early postnatal period but enhanced responses compared to controls at late postnatal period; whereas, male BPA and EE pups showed greater syllable duration compared to controls during early postnatal period. In mid-postnatal period, F2 BPA and EE pups emitted greater number of phrases than F2 control pups. Results indicate aspects of vocalizations were disrupted in F2 pups born to F1 parents developmentally exposed to BPA or EE, but their responses were not always identical, suggesting BPA might not activate estrogen receptors to the same extent as EE. Changes in vocalization patterns by F2 pups may be due to multigenerational exposure to BPA or EE and/or reduced parental care received. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
243. Genetic diversity of root system architecture in response to drought stress in grain legumes.
- Author
-
Heng Ye, Roorkiwal, Manish, Valliyodan, Babu, Lijuan Zhou, Pengyin Chen, Varshney, Rajeev K., and Nguyen, Henry T.
- Subjects
LEGUME genetics ,GRAIN ,DROUGHT tolerance ,PLANT roots ,CLIMATE change - Abstract
Climate change has increased the occurrence of extreme weather patterns globally, causing significant reductions in crop production, and hence threatening food security. In order to meet the food demand of the growing world population, a faster rate of genetic gains leading to productivity enhancement for major crops is required. Grain legumes are an essential commodity in optimal human diets and animal feed because of their unique nutritional composition. Currently, limited water is a major constraint in grain legume production. Root system architecture (RSA) is an important developmental and agronomic trait, which plays vital roles in plant adaptation and productivity under water-limited environments. A deep and proliferative root system helps extract sufficient water and nutrients under these stress conditions. The integrated genetics and genomics approach to dissect molecular processes from genome to phenome is key to achieve increased water capture and use efficiency through developing better root systems. Success in crop improvement under drought depends on discovery and utilization of genetic variations existing in the germplasm. In this review, we summarize current progress in the genetic diversity in major legume crops, quantitative trait loci (QTLs) associated with RSA, and the importance and applications of recent discoveries associated with the beneficial root traits towards better RSA for enhanced drought tolerance and yield. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
244. Auxin is Involved in Lateral Root Formation Induced by Drought Stress in Tobacco Seedlings.
- Author
-
Wang, Chengdong, Zhao, Yang, Meng, Lin, Song, Wenjing, Yang, Yinju, Wang, Shusheng, Gu, Pengyuan, Zou, Fuyu, and Zhang, Yali
- Subjects
AUXIN ,TOBACCO ,ROOT formation ,PLANT growth ,ACETIC acid - Abstract
Drought stress is a common abiotic stress that affects plant root development. The goal of this study was to identify the role of auxin on aspects of root growth under water-deficient conditions in
Nicotiana tabacum L. In this study, time-course development of lateral root (LR) growth in response to water deficiency (2.5% polyethylene glycol 6000, PEG) was analyzed in tobacco seedlings. LR formation in tobacco plants in response to drought stress depended on the experimental duration. First- and second-order LR formation was induced, respectively, by 43 and 28% on day 5 and by 57 and 40% on day 7 relative to control treatment. Thereafter, PEG-induced LR formation was not observed, and a decrease of 16% was recorded in first-order LR formation on day 11. A root pruning study suggested that PEG-induced LR formation plays a pivotal role in maintaining tobacco plant growth during drought stress. The change in the indole-3-acetic acid (IAA) concentration in leaves and roots was consistent with that of LR formation. This was corroborated by elevatedDR5::GUS expression levels on day 5 and by decreased expression levels on day 9. Application ofN -1-naphthylphthalamic acid (NPA) to PEG-treated seedlings reduced LR formation to levels similar to those of the control treatment;DR5::GUS expression was also similar between these treatments after NPA application. Results were similar following α-naphthylacetic acid application to control-treated seedlings. Measurement of [3 H]IAA transport indicated that polar auxin transport from shoots to roots was increased by 43% under PEG application. Quantitative reverse transcription PCR revealed higher expression ofYUC andPIN genes in PEG-treated plants, indicating that they play key roles in auxin synthesis and transport regulation in drought stress. Overall, these suggest that drought stress regulates LR formation in tobacco seedlings via modification of auxin synthesis and polar transport depending on the experimental stage. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
245. Identification of drought-induced genes in giant leucaena (<italic>Leucaena leucocephala</italic> subsp. <italic>glabrata</italic>).
- Author
-
Honda, Michael D. H., Ishihara, Kazue L., Pham, Dung T., and Borthakur, Dulal
- Abstract
Key message: A number of drought-induced genes have been identified from giant leucaena.Abstract:
Leucaena leucocephala subspecies glabrata (leucaena), which is also known as ‘giant leucaena’, is a multipurpose tree legume that can be grown and maintained as a woody tree for wood and paper pulp production, or as a shrubby legume through repeated harvest of foliage for use as a fodder. Leucaena is naturally resistant to most biotic and abiotic stresses including drought. The objective of this research was to identify drought-responsive genes in leucaena seedlings through microarray and qRT-PCR analyses. Ten thousand cDNA sequences selected from a leucaena transcriptome were screened for higher expression in a 4 × 180 k microarray using RNA isolated from drought-treated and untreated leucaena seedlings. Microarray analysis identified 73 and 39 drought-responsive genes sequences that were upregulated in the root and shoot, respectively. qRT-PCR analyses confirmed the root- and shoot-specific upregulation of some of the most highly expressed gene sequences identified in the microarray analysis. The proteins encoded by these genes could be grouped into four classes: (1) receptors that sense osmotic and oxidative stresses, (2) transcription factors, (3) degradation pathway enzymes, and (4) biosynthetic enzymes and structural proteins. The functions of these four classes of proteins can be used to explain the drought response in leucaena. The NB-LRR class of disease-resistance proteins may serve as receptors for detecting osmotic and oxidative stresses induced by drought, leading to induction of transcription factors such as zinc finger CCCH domain-containing protein and TCP14. As result, the genes for some degradative pathway enzymes, such as GDSL esterase/lipase, lipid acyl hydrolase patatin, and serine carboxypeptidase, were induced. Similarly, the expression of certain biosynthetic enzymes and structural proteins such as flavonoid 3-O-galactosyl transferase, caffeoyl-CoA O-methyltransferase, 9-cis-epoxy carotenoid dioxygenase, β-amyrin synthase, pentatricopeptide-containing protein, GPI-anchored protein COBRA, and peroxin, were also induced. High expression of some of these drought-inducible genes in leucaena seedlings may be used as a selection criterion in future breeding programs for drought resistance in leucaena and other legumes. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
246. Melatonin and serotonin: Mediators in the symphony of plant morphogenesis.
- Author
-
Erland, Lauren A. E., Shukla, Mukund R., Singh, Amritpal S., Murch, Susan J., and Saxena, Praveen K.
- Subjects
PHYSIOLOGICAL effects of melatonin ,HYPERICUM perforatum ,PLANT growth ,PLANT morphogenesis ,PLANT mutation breeding ,SEROTONIN - Abstract
Abstract: Melatonin and serotonin are important signaling and stress mitigating molecules that play important roles across growth and development in plants. Despite many well‐documented responses, a systematic investigation of the entire metabolic pathway (tryptophan, tryptamine, and
N ‐acetylserotonin) does not exist, leaving many open questions. The objective of this study was to determine the responses ofHypericum perforatum (L.) to melatonin, serotonin, and their metabolic precursors. Two well‐characterized germplasm lines (#4 and 112) created by mutation and a haploid breeding program were compared to wild type to identify specific responses. Germplasm line 4 has lower regenerative and photosynthetic capacity than either wild type or line 112, and there are documented significant differences in the chemistry and physiology of lines 4 and 112. Supplementation of the culture media with tryptophan, tryptamine,N ‐acetylserotonin, serotonin, or melatonin partially reversed the regenerative recalcitrance and growth impairment of the germplasm lines. Quantification of phytohormones revealed crosstalk between the indoleamines and related phytohormones including cytokinin, salicylic acid, and abscisic acid. We hypothesize that melatonin and serotonin function in coordination with their metabolites in a cascade of phytochemical responses including multiple pathways and phytohormone networks to direct morphogenesis and protect photosynthesis inH. perforatum . [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
247. Seminal bacterial composition in patients with obstructive and non‑obstructive azoospermia.
- Author
-
Chen, Houyang, Luo, Tao, Chen, Tingtao, and Wang, Gongxian
- Subjects
BACTERIAL disease treatment ,GUT microbiome ,ACTINOBACTERIA ,BACTEROIDETES ,MICROBIAL diversity ,NUCLEOTIDE sequencing - Abstract
A number of culture-dependent and -independent studies have reported that the number and significance of bacterial species in semen may have been underestimated. The aim of the present study was to profile the seminal microbiome in patients with obstructive or non‑obstructive azoospermia. A high‑throughput sequencing method was adopted to sequence genomic DNA extracted from the semen of healthy people (C group), patients with obstructive azoospermia (OA group) and patients with non‑obstructive azoospermia (NOA group). The results revealed that Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria species comprised the majority of bacteria in the C (98.14%), OA (98.26%) and NOA (90.96%) groups. Patients in the OA and NOA groups exhibited an increase in Bacteroidetes and Firmicutes, whereas the number of Proteobacteria and Actinobacteria were decreased compared with the C group. A total of 398 common operational taxonomic units were identified, of which 27 belonged to the genus Lactobacillus. Furthermore, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States analysis indicated that the pathogenic species and reduced biodiversity in the semen of patients with azoospermia may result in an increased risk of metabolic, infectious and immune diseases. In the present study, the seminal microbiome of patients with obstructive or non‑obstructive azoospermia was explored, which may be useful for developing novel treatments against azoospermia as well as for its diagnosis. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
248. Microbial Degradation of Forensic Samples of Biological Origin: Potential Threat to Human DNA Typing.
- Author
-
Dash, Hirak Ranjan and Das, Surajit
- Abstract
Forensic biology is a sub-discipline of biological science with an amalgam of other branches of science used in the criminal justice system. Any nucleated cell/tissue harbouring DNA, either live or dead, can be used as forensic exhibits, a source of investigation through DNA typing. These biological materials of human origin are rich source of proteins, carbohydrates, lipids, trace elements as well as water and, thus, provide a virtuous milieu for the growth of microbes. The obstinate microbial growth augments the degradation process and is amplified with the passage of time and improper storage of the biological materials. Degradation of these biological materials carriages a huge challenge in the downstream processes of forensic DNA typing technique, such as short tandem repeats (STR) DNA typing. Microbial degradation yields improper or no PCR amplification, heterozygous peak imbalance, DNA contamination from non-human sources, degradation of DNA by microbial by-products, etc. Consequently, the most precise STR DNA typing technique is nullified and definite opinion can be hardly given with degraded forensic exhibits. Thus, suitable precautionary measures should be taken for proper storage and processing of the biological exhibits to minimize their decaying process by micro-organisms. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
249. Steroids, stress and the gut microbiome‐brain axis.
- Author
-
Tetel, M. J., de Vries, G. J., Melcangi, R. C., Panzica, G., and O'Mahony, S. M.
- Subjects
STEROIDS ,GUT microbiome ,PSYCHOLOGICAL stress ,BRAIN physiology ,ANXIETY - Abstract
It is becoming well established that the gut microbiome has a profound impact on human health and disease. In this review, we explore how steroids can influence the gut microbiota and, in turn, how the gut microbiota can influence hormone levels. Within the context of the gut microbiome‐brain axis, we discuss how perturbations in the gut microbiota can alter the stress axis and behaviour. In addition, human studies on the possible role of gut microbiota in depression and anxiety are examined. Finally, we present some of the challenges and important questions that need to be addressed by future research in this exciting new area at the intersection of steroids, stress, gut‐brain axis and human health. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
250. Maize seedling performance as a potential index for drought tolerance.
- Author
-
Kravić, Natalija, Šukalović, Vesna Hadži-Tašković, Babić, Vojka, Srdić, Jelena, Mesarović, Jelena, and Anđelković, Violeta
- Subjects
DROUGHT tolerance of corn ,SEEDLINGS ,POLYETHYLENE glycol ,OSMOSIS ,EXPERIMENTAL agriculture ,PLANTS - Abstract
Twenty-six maize landraces were tested in order to evaluate maize seedling performance as an index for drought tolerance in adult plants. Samples were subjected to polyethylene glycol-induced osmotic stress at the early seedling stage. Grain yield was obtained in field experiments under well-watered (OC) and a combination of drought and high plant density (HD) conditions. Osmotic stress caused a reduction in seedling growth (length, fresh and dry weight), and increase in the shoot and in particular the root proline contents in the majority of landraces, and variations in root peroxidase (POD) activity. Genotypes displaying more pronounced root growth reduction and higher proline contents exhibited decreased POD activity under osmotic stress. Direct positive correlations between the proline content and growth inhibition, and between the proline and soluble protein content were established. Correlations between the changes in POD activity and growth parameters were significant and positive, and significant but negative with the changes in the proline content. In the field, water stress led to a reduction in grain yield in all of the tested landraces. Correlations between grain yield from both experimental sets (OC and HD) and osmotic-induced changes in seedling root growth were negative, which was opposite to the highly significant and positive correlations between the changes in the seedling root proline content and yield. Also, genotypes with the highest seedling root proline content increase under osmotic stress, exhibited the highest stress tolerance index (STI) based on grain yield achieved under both field conditions. Our results indicate that lower changes in POD activity and especially an increased proline content after exposure to osmotic stress during the early seedling stage could be considered as useful indices to facilitate selection efficiency for drought tolerance in adult plants. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.