Search

As a highly conserved family of plant-specific proteins, SIMILAR-TO-RCD-ONE (SROs) play an essential role in plant growth, development and response to abiotic stresses. In this study, six StSRO genes were identified by searching the PARP, RST and WWE domains based on the genome-wide data of potato database DM v6.1, and they were named StSRO1–6 according to their locations on chromosomes. StSRO genes were comprehensively analyzed using bioinformatics methods. The results showed that six StSRO genes were irregularly distributed on five chromosomes. Phylogenetic analysis showed that 30 SRO genes of four species were distributed in three groups, while StSRO genes were distributed in groups II and III. The promoter sequence of StSRO genes contained many cis-acting elements related to hormones and stress responses. In addition, the expression level of StSRO genes in different tissues of doubled monoploid (DM) potato, as well as under salt, drought stresses and hormone treatments, was analyzed by RNA-seq data from the online database and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Furthermore, the expression level of StSRO genes was analyzed by transcriptome analysis under mild, moderate and severe salt stress. It was concluded that StSRO genes could respond to different abiotic conditions, but their expression level was significantly different. This study lays a foundation for further studies on the biological functions of the StSRO gene family.

The DWARF4 (DWF4) gene encodes a C-22 hydroxylase which is pivotal for brassinosteroids (BRs) biosynthesis. In this research, aimed to understand the molecular mechanism of DWF4 on regulation of potatoes tolerance to salt stress, DWF4 was cloned from potato, named as StDWF4. Its 1476 bp open reading frame encodes a protein of 491 amino acids. The StDWF4-overexpressing (OE) and interference-expressing (RNAi) transgenic potato plants were acquired using Agrobacterium-mediated transformation, respectively. Tissue specific analysis using Quantitative real-time polymerase chain reaction (qRT-PCR) demonstrated that the StDWF4 gene expressed in the leaves, stems and roots of the transgenic and un-transgenic (NT) plants, with specially increased (StDWF4-OE)/reduced (StDWF4-RNAi) expression in the roots. The content of malondialdehyde (MDA) in StDWF4-OE potato plants was lower than that of NT, and proline content was higher than that of NT. MDA and proline content in StDWF4-OE and NT under salt-stress was significantly higher than that of the control and was increased at different sampling times. The content of soluble protein, soluble sugar and the activities of superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) was higher in the StDWF4-OE plantlets at varied salt treatment time than in the NT potatoes. Reduction of H2O2 content in the StDWF4-OE plants was observed. All above plant physiology indicators in the StDWF4-RNAi potatoes showed opposite variation trends. The results proved that the overexpressing of StDWF4 in potato plantlets can enhance the salt resistance by alleviating the negative effects of salt-stress. However, its interference expression in potato plants depresses the salt resistance. The results lay the groundwork for intensive study of BRs regulation in potato growth and development, and will help us to reveal the molecular mechanisms of how the BRs signaling regulate potato salt tolerance.

The eigenstate of the Optical Transfer Function (OTF) theory is cosine fringe. In the non-Fourier transform OTF theory, the emission field of the cosine fringe is decomposed into an ensemble of interference pairs. In this paper, we use the interference theory of light to study the parameters of the two light beams of the interference pair. Afterward, we discuss the reflection coefficient of the cosine fringe and obtain the conclusion that the cosine fringe is a complex number. In addition, we analyze the interaction which is between illumination light and cosine fringe to obtain the state of the surface wave and its emission field, which reveals the mechanism of cosine fringe emission interference pairs. Furthermore, by comparing the interaction between illumination light and cosine fringe with communication modulation theory, we confirm that the principle of cosine fringe emission interference pairs is the same as that of Double-sideband suppressed-carrier. Finally, the optical imaging is analyzed by using the concept of photon ensemble, and come to the conclusion that ideal imaging does not exist. The work of this paper not only provides a basis for the non-Fourier transform OTF theory, but also contributes the illumination design of optical imaging systems.

This article draws on a neurofunctional theory of bilingual processing and its application to translation to investigate the dominant cognitive processing route in the literary and subtitle translation and also differences of the dominant patterns between the two translation modes, specifically those involving Chinese-English language pairs. This general investigation has two specific aims: 1) to extract the translation strategy patterns at the textual level and 2) to determine the dominant processing route at the cognitive level by linking the strategies to processing routes. Building on naturalistic translational data, a bilingual corpus was self-built; the linguistic features of the translated products were analyzed. The current study analyzes the renderings of Chinese culture-specific items into English. The results suggest that the dominant processing pattern can be identified in both the literary and subtitle translation. Moreover, based on the empirical evidence, it is found that the meaning-based processing route dominates both literary and subtitle translation. This article concludes that the contextual-intentional-conceptual system handles culture-specific concepts through conceptual mediation, which is required in the translation process due to contextual and pragmatic factors. The issue of cognitive processing routes that may take place in the translator’s brain is of significance to translation process research specifically and translation studies in general.

Traditional breeding has been widely used and will remain crucially important for agricultural production. However, traditional breeding technology only improves crops to a certain level because it relies on the endogenous or population gene pools. Transgenic technology can overcome species or outcrossing barriers, and enlarge the gene pools in crops. Genetically modified (GM) crops can act as a powerful complement to the crops produced by conventional breeding methods to meet the worldwide demand for quality foods. This chapter is an attempt to summarize the recent progress and new advances in improvement of tuber and root crops (including potato, sweet potato, taro, ginger, and turmeric) using GM technology. The biosafety issues involved in transgenic tuber and root crops and future prospects using GM technology are also discussed.

Plant microRNAs are important endogenous gene regulators which regulate gene expression at post-transcriptional level. Previous studies have identified that miR169 family members regulated the NF-YA transcription factors which have been implicated in plant development and stress responses. At present, reported potato genome sequence data offered an opportunity for global insights into the molecular mechanisms of the miR169/NF-YA modules in potato. In this work, 4 novel stu-miR169 family members were predicted in potato based on potato genome sequence data. miRNA target prediction showed that mature stu-miR169 sequences have a bite sit on the 5 of StNF-YA genes in potato, and three of them were validated by RNA ligase-mediated 5′RACE (5′ RLM-RACE) assay. The result from investigation of the expression patterns of mature stu-miR169 and their predicted target genes also showed that mature stu-miR169 was down-regulated in response to the drought stress. There were some targeted StNF-YA genes that exhibited a negative expression pattern with mature stu-miR169 during the different periods of drought-treated samples. Taken together, the decreased expression of stu-miR169 might drive over-expression of NF-YA family members, they are related to resistances against drought stress.

Ethylene response factor (ERF) is a major subfamily of the AP2/ERF family and plays significant roles in the regulation of abiotic- and biotic-stress responses. ERF proteins can interact with the GCC-box cis-element and then initiate a transcriptional cascade activating downstream ethylene response and enhancing plant stress tolerance. In this research, we cloned five StERF genes from potato (Solanum tuberosum L.). The expressional analysis of StERF genes revealed that they showed tissue- or organ-specific expression patterns and the expression levels in leaf, stem, root, flower, and tuber were different. The assays of quantitative real-time polymerase chain reaction (qRT-PCR) and the reverse transcription-PCR (RT-PCR) showed that the expression of five StERF genes was regulated by ethephon, methyl jasmonate (MeJA), salt and drought stress. The result from the yeast one-hybrid experiment showed that five StERFs had trans-activation activity and could specifically bind to the GCC-box cis-elements. The StERFs responded to abiotic factors and hormones suggested that they possibly had diverse roles in stress and hormone regulation of potato.

The cerium oxide nanoparticles (NPs) have been widely used in the fields of fuel additives, cosmetics, commodities, pharmaceuticals and other industries. Exposure of the CeO2 NPs causes a public concern on their potential health risk. In this study, the interactions between two commercial CeO2 NPs and human bronchoalveolar carcinoma-derived A549 cells were investigated to provide a fast and in-depth understanding of the biological influences of the NPs. In the culture medium containing 10% fetal bovine serum, both of the D-CeO2 and PC-CeO2 NPs had an extremely small solubility (< 0.1 ng/mL) and were aggregated from 20 nm and 8 nm (in a dry state) to approximately 190 nm and approximately 60 nm, respectively. Both types of the CeO2 NPs showed slightly negative surface charge due to the adsorption of serum proteins. They had rather weak cytotoxicity even at the highest concentration of 200 microg/mL. Cellular uptake of the CeO2 NPs increased along with the increase of concentration and incubation time. The internalized CeO2 NPs were dispersed in vacuoles and cytoplasm. Uptake of the particles resulted in slight change of the cell cycles, i.e., more cells stayed in the G1 phase, and could suppress the production of reactive oxygen species but brought negligible influence on the mitochondrial membrane potential. However, the cytoskeleton organization and the cell adhesion ability were affected to some extent.

Aphids, the largest group of sap-sucking pests, cause significant yield losses in agricultural crops worldwide every year. The massive use of pesticides to combat this pest causes severe damage to the environment, putting in risk the human health. In this study, transgenic potato plants expressing Galanthus nivalis agglutinin ( GNA ) gene were developed using CaMV 35S and ST-LS1 promoters generating six transgenic lines (35S1-35S3 and ST1-ST3 corresponding to the first and second promoter, respectively). Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the GNA gene was expressed in leaves, stems and roots of transgenic plants under the control of the CaMV 35S promoter, while it was only expressed in leaves and stems under the control of the ST-LS1 promoter. The levels of aphid mortality after 5 days of the inoculation in the assessed transgenic lines ranged from 20 to 53.3%. The range of the aphid population in transgenic plants 15 days after inoculation was between 17.0 ± 1.43 (ST2) and 36.6 ± 0.99 (35S3) aphids per plant, which corresponds to 24.9–53.5% of the aphid population in non-transformed plants. The results of our study suggest that GNA expressed in transgenic potato plants confers a potential tolerance to aphid attack, which appears to be an alternative against the use of pesticides in the future.

This study is focused on the uptake of PLGA particles with different coatings and its influences on the functions and toxicity of human endothelial cells. The PLGA particles coated with polyethyleneimine (PEI) or bovine serum albumin (BSA) were prepared via a one-step emulsion method, which had a similar diameter of ∼420 nm in water and ∼170 nm in a dry state but oppositely charged surfaces. Both types of the particles were readily internalized into cells within a short time regardless of their surface chemistry. Uptake of the positively charged particles caused apparently a decrease in cell viability, but did not significantly influence mitochondrial membrane potential and activity of caspase-3. The cell adhesion and migration were significantly affected, especially after uptake of the PLGA-PEI particles. The secretion levels of von Willebrand factor (vWF) and 6-k-PGF(1α) were not significantly influenced regardless of the surface coating.

Glucose is the main energy source for mammalian cells and its absorption is co-mediated by two different families of glucose transporters, sodium/glucose co-transporters (SGLTs) and facilitative glucose transporters (GLUTs). Here, we report the cloning and tissue distribution of porcine GLUT2. The GLUT2 was cloned by RACE and its cDNA was 2,051 bp long (GenBank accession no. EF140874). An AAATAA consensus sequence at nucleotide positions 1936-1941 was located upstream of the poly (A) + tail. Open reading frame analysis suggested that porcine GLUT2 contained 524 amino acids, with molecular weight of 57 kDa. The amino acid sequence of porcine GLUT2 was 87% and 79.4% identical with human and mouse GLUT2, respectively. GLUT2 mRNA was detected at highest level in porcine liver, at moderate levels in the small intestine and kidney, and at low levels in the brain, lung, muscle and heart. In the small intestine, the highest level was in the jejunum. In conclusion, the mRNA expression of GLUT2 was not only differentially regulated by age, but also differentially distributed along the small intestine of piglets, which may be related to availability of different intestinal luminal substrate concentrations resulting from different food sources and digestibility.

In this study, we cloned, sequenced and characterized porcine y+L Amino Acid Transporter-1 (y+LAT1). By screening a translated EST database with the protein sequence of the human y + LAT1 and by using rapid amplification of cDNA ends (RACE), the full-length cDNA encoding porcine y + LAT1 was isolated from porcine intestine RNA. It was 2,111 bp long, encoding a 511 amino acid trans-membrane glycoprotein composed of 12 transmembrane domains. The predicted amino acid sequence was found to be 91%, 90%, 87% and 87% identical to those of cattle, human, mouse and rat y + LAT1 respectively. Real-time RT-PCR results indicated that the small intestine had the highest y + LAT1 mRNA abundance and the lung had the lowest y + LAT1 mRNA abundance. Baby hamster kidney (BHK) cells transfected with green fluorescent protein (GFP) tagged porcine y + LAT1 cDNA indicated that the cellular localization of the gene product in BHK was on the plasma membrane.

The goal of this study was to elucidate the expression and segmental distribution of the glomerular cationic amino acid metabolism transporter-2 (CAT-2) and thus to improve our understanding of porcine cationic amino acid transporters and amino acid absorption. Porcine CAT-2 was cloned, sequenced and characterized. The predicted amino acid sequence of porcine CAT-2 shared 86.1% and 92.1% identity with human and mouse CAT-2A, respectively. The tissue distribution patterns and ontogenic changes of CAT-2 mRNAs were determined by real-time Q-PCR. The results showed that porcine CAT-2 was highly expressed in the heart and intestinal tract (duodenum, ileum and jejunum). In addition, the mRNA of CAT-2 was found in liver, lung, kidney, brain and muscle. Within the intestinal tract, CAT-2 mRNA was most abundant in the ileum and rarely expressed in the duodenum. In the duodenum, the levels of CAT-2 mRNA reached their peak on day 7 (p

Molecular cloning, tissue distribution and ontogenetic regulation of sodium/proton exchanger isoform 2 (NHE-2) mRNA expression were evaluated in the pig small intestine during postnatal development. The 2872-bp porcine full cDNA sequence of the NHE-2 (EF672046) cloned in this study showed 80% and 70% homology with known human and mouse gene sequence, respectively. Hydrophobic prediction suggests 13 putative membrane-spanning domains within porcine NHE-2. The porcine NHE-2 mRNA was detected in the brain, liver, kidney, heart, lung, small intestine and muscle. The small intestine had the highest NHE-2 mRNA abundance and the brain, lung and liver had the lowest NHE-2 mRNA abundance (P < 0.05). Along the longitudinal axis, the duodenum had the highest NHE-2 mRNA abundance and the ileum and colon had the lowest NHE-2 mRNA abundance (P < 0.05). The NHE-2 mRNA level was increased from day 1 to day 26 in the duodenum (P < 0.05) and dropped dramatically on day 30 (P < 0.05). There is no difference between day 1 and day 7 (P > 0.05). After day 30, the NHE-2 mRNA level remained the same except on day 90 (P > 0.05). The mRNA expression of NHE-2 was not only differentially regulated by age but also differentially distributed along the small intestine of piglets at early stages and growing stages of life, which may contribute to changes in NHE activity.

BACKGROUND: Segmental distribution and expression of two heterodimeric amino acid transporter mRNAs during different ages were evaluated in pigs along the horizontal axis of the intestine. RESULTS: The intestinal distribution of b0, + AT and y+LAT1 mRNA at day 90 showed that for b0, + AT the mRNA levels were increased from the proximal to distal part of the small intestine (P < 0.05) and dropped dramatically in colon (P < 0.05). The ileum had the highest b0, + AT mRNA abundance and the ileum had the lowest. Compared to b0, + AT, the y+ LAT1 mRNA levels were decreased from the proximal to distal part of the small intestine (P < 0.05). The duodenum has the highest y+ LAT1 mRNA abundance. The mRNA abundance of b0, + AT mRNA increased linearly (P < 0.0001) from day 1 to day 150 in ileum. CONCLUSION: The mRNA expression of heterodimeric amino acid transporters (b0, + AT and y+LAT1) was not only differentially regulated by age but also differentially distributed along the intestine of piglets at early stages and growing stages of life, which may be related to luminal substrate concentration as well as amino acid requirement and hormones. Copyright © 2008 Society of Chemical Industry

Exposure of the CeO2 nanoparticles (NPs) causes a public concern on their potential health risk due to their wide applications in the fields of fuel additive, commodities, pharmaceutical, and other industries. In this study, the interactions between two commercial CeO2 NPs (D-CeO2 from Degussa and PC-CeO2 from PlasmaChem) and mouse leukemic monocyte macrophage Raw264.7 cells were investigated to provide a fast and in-depth understanding of the biological influences of the NPs. Both types of the CeO2 NPs had a negative surface charge around −12 mV and showed a tendency to form aggregates with sizes of 191 ± 5.9 and 60.9 ± 2.8 nm in cell culture environment, respectively. The cellular uptake of the CeO2 NPs increased along with the increase of feeding dosage and prolongation of the culture time. The PC-CeO2 NPs had a faster uptake rate and reached higher cellular loading amount at the highest feeding concentration (200 µg/mL). In general, both types of the CeO2 NPs had rather small cytotoxicity even with a dosage as high as 200 µg/mL. The D-CeO2 NPs showed a relative stronger cytotoxicity especially at higher concentrations and longer incubation time. The NPs were dispersed in vacuoles (most likely endosomes and lysosomes) and cytoplasm. Although both types of the CeO2 NPs could suppress the production of reactive oxygen species, they impaired the mitochondria membrane potential to some extent. The cytoskeleton organization was altered and consequently the cell adhesion ability decreased after uptake of both types of the CeO2 NPs.

Noble-metal nanoparticles (NPs) especially prepared from gold and silver have been combined on the surface of graphene to obtain graphene-based nanocomposites for novel functions in enhanced performance in bio-imaging, cancer detection and therapy. However, little is known about their cellular uptake, especially the intracellular quantity which plays a critical role in determining their functions and safety. Therefore, we prepared covalently conjugated GO/Au and GO/Ag composites by immobilizing Au and Ag nanoparticles on GO sheets pre-functionalized with disulfide bonds, respectively. The cellular uptake of these composites was quantitatively studied by means of an ion beam microscope (IBM) to determine the metal content in human lung cancer cells (A549 cells) and liver hepatocellular carcinoma cells (HepG2 cells). The cell uptake was also studied by inductively coupled plasma mass spectrometry (ICP-MS), which is one of the most sensitive techniques being applied to cell suspensions, for comparison. Toxicity, one of the consequences of cellular uptake of GO based composites, was studied as well. The potential toxicity mechanism was also suggested based on the results of intracellular quantification of the nanomaterials.

The complexation between a water-soluble pillar[6]arene (WP6) and paraquat (G1) in water was investigated. They could form a stable 1:1 [2]pseudorotaxane with an extremely high association constant of (1.02 ± 0.10) × 10(8) M(-1) mainly driven by electrostatic interactions, hydrophobic interactions, and π-π stacking interactions. This molecular recognition has not only high binding strength but also pH-responsiveness. The threading and dethreading processes of this [2]pseudorotaxane could be reversibly controlled by changing the solution pH. This novel recognition motif was further used to control the aggregation of a complex between WP6 and an amphiphilic paraquat derivative (G2) in water. The reversible transformations between micelles based on G2 and vesicles based on WP6⊃G2 were realized by adjusting the solution pH due to the pH-responsiveness of WP6. The controlled release of water-soluble dye molecules from the vesicles could be achieved by the collapse of the vesicles into the micelles upon changing the solution pH to acidity. Additionally, the high binding affinity between WP6 and paraquat could be utilized to efficiently reduce the toxicity of paraquat. After the formation of a stable host-guest complex between WP6 and paraquat, less opportunity was available for paraquat to interact with the reducing agents in the cell, which made the generation of its radical cation more difficult, resulting in the efficient reduction of paraquat toxicity.

The molecular structure and physicochemical properties of nano- and colloidal materials have a big impact on their intracellular uptake and cell functions. Elucidation of the cellular uptake and cytotoxicity of the colloidal materials has been recognized recently as one of the paramount prerequisites for their biomedical applications. In this review, the influence of important parameters of colloidal biomaterials such as size, shape, chemical and mechanical properties on cellular uptake and its pathways is summarized. The intracellular distribution and transportation of the colloidal particles are then correlated with their physiochemical properties. The impacts on cytotoxicity and cell functions are also discussed. Finally, more attention is suggested to be paid on the basic understanding of cellular uptake and subsequent influence on cells, which is of great significance for the function implementations and safer applications of nano- and colloidal materials.

Pregnant mice were whole-body irradiated with a single acute dose of gamma-rays (60Co) to investigate the effect of gamma-radiation on embryonic melanoblasts. The effect was studied by scoring changes in the differentiation of melanocytes in the hair follicles of mice heterozygous for the recessive coat color mutation pink-eyed dilution (p). Abnormal round melanocytes were found in the hair matrix and the dermal papilla of F1 offspring 3.5 days after birth. However, these round melanocytes possessed a melanin deposition of similar intensity to normal hair follicular melanocytes. The frequency of the abnormal hair follicles increased in a dose-dependent manner. Moreover, higher frequencies were found in the animals irradiated at earlier stages of embryonic development. These results indicate that gamma-radiation affects dendritogenesis and the location of mouse melanocytes in the hair follicles, with greater effects seen at the earlier stages of development.