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Compensating for the pitch error in the scanning movement is a fundamental issue when conducting large-scale surface shape measurements with deflectometric profilers. This paper presents a new long trace profiler employing a shearing measurement technique. In this setup, the optical head and the mirror under test are mounted on two independent parallel movable air-bearing carriages to enable shearing and scanning movements separately. The distance between the optical head and the tested mirror remains fixed, effectively minimizing the influence of system errors resulting from imperfections in optical devices. Simulation studies show that the double shear measurement method with a low-spatial-frequency filtering process can effectively mitigate high-frequency angular measurement errors introduced by the instability of the air-bearing stage. Experimental tests conducted on flat mirrors demonstrated a precision of less than 50 nrad rms, thereby confirming the robustness of the system., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

This paper presents the first-principles design approach for x-ray active optics. The feature of deterministic modulation enables the simulation-modulation cycle in place of the measurement-modulation feedback loops used in traditional active optics. We apply an x-ray mirror with localized thermal elastic deformation to validate the idea. Our experiments have demonstrated that the new active optics have the potential to outperform the accuracy of surface shape metrology instruments.

A single-point-probe-based slope profiler is a common measurement scheme for the measurement of freeform optical surfaces, which has been a challenging research direction. Efficiency is a key issue in two-dimensional scanning-based measurement. This study establishes a measurement system simulation model and reveals that the height reconstruction accuracy of different reconstruction algorithms is primarily correlated with the sampling density. The spatial resolution calibrated of the slope measurement device is also identified to be an essential part of the strategy. Based on a kind of slope profiler, this paper applies variable sampling intervals for different spatial frequency characteristics of the surface under test (SUT). The result shows that the reconstruction accuracy can be controlled by selecting sampling parameters and calibrating the slope measurement device. For objects with different spatial characteristics, targeted optimization of the measurement scheme can be achieved. This strategy also has a certain universality for general scanning slope measurement and height reconstruction, providing a reference for device selection and sampling settings for different spatial frequency measurement requirements.

Introduction: The role of submucosal injection during cold snare polypectomy (CSP) remains uncertain. In this study, we investigated the impact of submucosal saline injection during CSP for colorectal polyps sized 3-9 mm., Methods: This was a multicenter randomized controlled trial conducted in 6 Chinese centers between July and September 2020 (ChiCTR2000034423). Patients with nonpedunculated colorectal polyps sized 3-9 mm were randomized in a 1:1 ratio to either CSP with submucosal injection (SI-CSP) or conventional CSP (C-CSP). The primary outcome was the incomplete resection rate (IRR). Secondary outcomes included procedure time, intraprocedural bleeding, delayed bleeding, and perforation., Results: One hundred fifty patients with 234 polyps in the SI-CSP group and 150 patients with 216 polyps in the C-CSP group were included in the analysis. The IRR was not decreased in the SI-CSP group compared with that in the C-CSP group (1.7% vs 1.4%, P = 1.000). The median procedure time in the SI-CSP group was significantly longer than that in the C-CSP group (108 seconds vs 48 seconds, P < 0.001). The incidences of intraprocedural bleeding and delayed bleeding were not significantly different between the 2 groups ( P = 0.531 and P = 0.250, respectively). There was no perforation in either group., Discussion: Submucosal saline injection during CSP for colorectal polyps sized 3-9 mm did not decrease the IRR or reduce adverse events but prolonged the procedure time., (Copyright © 2023 by The American College of Gastroenterology.)

Plant elicitor peptides (Peps) are recognized by two receptor-like kinases, PEPR1 and PEPR2, and trigger plant immunity responses and root growth inhibition. In this study, we reveal that the Pep-PEPR system triggers root immunity responses in Arabidopsis. Pep1 incubation initiated callose and lignin deposition in roots of wild type but not in that of pepr1 pepr2 mutant seedlings. The plasma membrane-associated kinase BIK1, which serves downstream of the Pep-PEPR signaling pathway, was essential for Pep1-induced root immunity responses. Interestingly, disruption of PEPR1/2-associated coreceptor BAK1 enhanced the deposition of both callose and lignin induced by Pep1 in roots. Ethylene and salicylic acid signaling are involved in Pep1-induced root immunity responses. Furthermore, we showed that the successful phytopathogen, P. syringae (DC3000) could effectively suppress Pep1-trigged root callose and lignin accumulation. These results demonstrated the endogenous Pep-triggered root immunity responses and pathogenic suppression of the Pep-PEPR signaling pathway., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Magnolia hypoleuca Sieb. & Zucc , a member of the Magnoliaceae of magnoliids, is one of the most economically valuable, phylogenetic and ornamental tree species in Eastern China. Here, the 1.64 Gb chromosome-level assembly covers 96.64% of the genome which is anchored to 19 chromosomes, with a contig N50 value of 1.71 Mb and 33,873 protein-coding genes was predicted. Phylogenetic analyses between M. hypoleuca and other 10 representative angiosperms suggested that magnoliids were placed as a sister group to the eudicots, rather than sister to monocots or both monocots and eudicots. In addition, the relative timing of the whole-genome duplication (WGD) events about 115.32 Mya for magnoliid plants. M. hypoleuca was found to have a common ancestor with M. officinalis approximately 23.4 MYA, and the climate change of OMT (Oligocene-Miocene transition) is the main reason for the divergence of M. hypoleuca and M. officinalis , which was along with the division of Japanese islands. Moreover, the TPS gene expansion observed in M. hypoleuca might contribute to the enhancement of flower fragrance. Tandem and proximal duplicates of younger age that have been preserved have experienced more rapid sequence divergence and a more clustered distribution on chromosomes contributing to fragrance accumulation, especially phenylpropanoid, monoterpenes and sesquiterpenes and cold tolerance. The stronger selective pressure drived the evolution of tandem and proximal duplicates toward plant self-defense and adaptation. The reference M. hypoleuca genome will provide insights into the evolutionary process of M. hypoleuca and the relationships between the magnoliids with monocots and eudicots, and enable us to delve into the fragrance and cold tolerance produced by M. hypoleuca and provide more robust and deep insight of how the Magnoliales evolved and diversified., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhou, Hou, Wang, Zhang, Wang, Yin, Pei, Peng, Qin and Gao.)

The kiwifruit ( Actinidia arguta var. purpurea) produces oval shaped fruits containing a slightly green or mauve outer exocarp and a purple-flesh endocarp with rows of tiny black seeds. The flesh color of the fruit results from a range of anthocyanin compounds, and is an important trait for kiwifruit consumers. To elucidate the molecular mechanisms involved in anthocyanin biosynthesis of the sarcocarp during A. arguta fruit development, de novo assembly and transcriptomic profile analyses were performed. Based on significant Gene Ontology (GO) biological terms, differentially expressed genes were identified in flavonoid biosynthetic and metabolic processes, pigment biosynthesis, carbohydrate metabolic processes, and amino acid metabolic processes. The genes closely related to anthocyanin biosynthesis, such as phenylalanine ammonia-lyase ( PAL ), chalcone synthase ( CHS ), and anthocyanidin synthase ( ANS ), displayed significant up-regulation during fruit development according to the transcriptomic data, which was further confirmed by qRT-PCR. Meanwhile, a series of transcription factor genes were identified among the DEGs. Through a correlation analysis. AaMYB1 was found to be significantly correlated with key genes of anthocyanin biosynthesis, especially with CHS . Through a transient expression assay, AaMYB1 induced anthocyanin accumulation in tobacco leaves. These data provide an important basis for exploring the related mechanisms of sarcocarp anthocyanin biosynthesis in A. arguta . This study will provide a strong foundation for functional studies on A. arguta and will facilitate improved breeding of A. arguta fruit., Competing Interests: The authors declare no conflict of interest.

Competing Interests: The authors declare that they have no conflict of interest.

Pseudomonas syringae pv. actinidiae (Psa), a bacterial pathogen, is a severe threat to kiwifruit production. To elucidate the species-specific interaction between Psa and kiwifruit, transcriptomic-profiles analyses were conducted, under Psa-infected treatment and mock-inoculated control, on shoots of resistant Maohua (MH) and susceptible Hongyang (HY) kiwifruit varieties. The plant hormone-signal transduction and plant-pathogen interaction were significantly enriched in HY compared with MH. However, the starch and sucrose metabolism, antigen processing and presentation, phagosome, and galactose metabolism were significantly enriched in MH compared with HY. Interestingly, the MAP2 in the pathogen/microbe-associated molecular patterns (PAMPs)-triggered immunity (PTI) was significantly up-regulated in MH. The genes RAR1, SUGT1, and HSP90A in the effector-triggered immunity (ETI), and the NPR1 and TGA genes involved in the salicylic acid signaling pathway as regulatory roles of ETI, were significantly up-regulated in HY. Other important genes, such as the CCRs involved in phenylpropanoid biosynthesis, were highly expressed in MH, but some genes in the Ca 2+ internal flow or involved in the reactive oxygen metabolism were obviously expressed in HY. These results suggested that the PTI and cell walls involved in defense mechanisms were significant in MH against Psa infection, while the ETI was notable in HY against Psa infection. This study will help to understand kiwifruit bacterial canker disease and provide important theoretical support in kiwifruit breeding.

Farmed animals produce excrement containing excessive amounts of toxic heavy metals as a result of consuming compound feed as well as receiving medical treatments, and the presence of these heavy metals may aggravate the risk of spreading drug-resistance genes through co-selection during manure treatment and application processes. However, research on the association between heavy metals and antimicrobial resistance is still lacking. In this study, metagenomic sequencing was used to explore the effects of the co-selection of environmentally toxic heavy metals on the resistome in manure. A relevance network analysis showed that metal-resistance genes (MRGs), especially for copper (Cu) and zinc (Zn), were positively correlated with multiple types of antibiotic-resistance genes (ARGs) and formed a complex network. Most bacteria that co-occurred with both MRGs and ARGs simultaneously are members of Proteobacteria and accounted for 54.7% of the total microbial species in the relevance network. The remaining bacteria belonged to Firmicutes, Bacteroidetes and Actinobacteria. Among the four phyla, Cu- and Zn-resistance genes had more complex correlations with ARGs than other MRG types, reflecting the occurrence of ARG co-selection under the selective pressure of high Cu and Zn levels. In addition, approximately 64.8%, 59.1% and 68.4% of MRGs that correlated with the presence of plasmids, viruses and prophages, respectively, are Cu- or Zn-resistant, and they co-occurred with various ARGs, indicating that mobile genetic elements participate in mediating ARG co-selection in response to Cu and Zn pressure. The results indicated that the use of heavy-metal additives in feed induces the increases of drug resistance genes in manure through co-selection, aggravating the risk of antimicrobial resistance diffusion from animal farm to manure land applications., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

In both plant and animal innate immune responses, surveillance of pathogen infection is mediated by membrane-associated receptors and intracellular nucleotide-binding domain and leucine-rich-repeat receptors (NLRs). Homeostasis of NLRs is under tight multilayered regulation to avoid over-accumulation or over-activation, which often leads to autoimmune responses that have detrimental effects on growth and development. How NLRs are regulated epigenetically at the chromatin level remains unclear. Here, we report that SWP73A, an ortholog of the mammalian switch/sucrose nonfermentable (SWI/SNF) chromatin-remodeling protein BAF60, suppresses the expression of NLRs either directly by binding to the NLR promoters or indirectly by affecting the alternative splicing of some NLRs through the suppression of cell division cycle 5 (CDC5), a key regulator of RNA splicing. Upon infection, bacteria-induced small RNAs silence SWP73A to activate a group of NLRs and trigger robust immune responses. SWP73A may function as a H3K9me2 reader to enhance transcription suppression., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Ambient fine particulate matter (PM 2.5 ) exposure correlates with adverse cardiometabolic effects. The underlying mechanisms have not yet been fully understood. Hypothalamic-pituitary-adrenal (HPA) axis, as the central stress response system, regulates cardiometabolic homeostasis and is implicated in the progression of various adverse health effects caused by inhalational airborne pollutant exposure. In this study, we investigated whether ambient PM 2.5 exposure activates HPA axis and its effect mediating PM 2.5 -induced pulmonary inflammation. C57Bl/6 J mice were intratracheally instilled with different concentrations of diesel exhaust PM 2.5 (DEP), and plasma was harvested at different times. Assessments of plasma stress hormones revealed that DEP instillation dose- and time-dependently increased mouse circulating corticosterone and adrenocorticotropic hormone (ACTH) levels, strongly supporting that DEP instillation activates HPA axis. To determine which components of DEP activate HPA axis, C57Bl/6J mice were intratracheally instilled with water-soluble and -insoluble fractions of DEP. Plasma analyses showed that water-insoluble but not -soluble fraction of DEP increased circulating corticosterone and ACTH levels. Consistently, concentrated ambient PM 2.5 (CAP) exposure significantly increased mouse urine and hair corticosterone levels, corroborating the activation of HPA axis by ambient PM 2.5 . Furthermore, deletion of stress hormones by total bilateral adrenalectomy alleviated PM 2.5 -induced pulmonary inflammation, providing insights into the contribution of central neurohormonal mechanisms in modulating adverse health effects caused by exposure to PM 2.5 ., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Ammonia (NH 3 ) volatilization in rice paddies may be affected by elevated atmospheric CO 2 concentration ([CO 2 ]) and temperature due to changes in plant and soil nitrogen (N) metabolism. At present, little is known about the individual and combined effects of CO 2 enrichment and warming on NH 3 volatilization under field conditions. An experiment was conducted in a rice paddy in Central China, after 4 years of warming and CO 2 enrichment using open-top chamber (OTC) devices. Compared with ambient conditions, elevated [CO 2 ] had no significant effects on NH 3 volatilization, although increases in soil pH and urease activity were observed. The stimulation on plant N assimilation under CO 2 enrichment might offset the possible enhancement on NH 3 volatilization, as more soil N was absorbed by plant thus reducing NH 3 loss potential. Elevated temperature increased NH 3 volatilization significantly, which could be attributed to increased soil ammonium nitrogen (NH 4 + -N) concentration, pH, and urease activity. Combination of CO 2 enrichment and warming caused the highest cumulative NH 3 loss, which increased by 26.5% compared with ambient conditions, but the interaction was not significant. Higher plant N uptake, soil NH 4 + -N concentration, pH and urease activity were also observed with co-elevation of [CO 2 ] and temperature, but the combined effects were variable and not synergistic. Our findings confirm that field warming and CO 2 enrichment cause more NH 3 volatilization in rice paddies, among which warming effects are dominant, and suggest that improved N management or field practices are required to reduce NH 3 losses under future climate change., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Copyright © 2020. Published by Elsevier B.V.)

Cervical cancer (CC) is a common malignant tumor among women worldwide, remaining the fourth most frequent cause of cancer death in women. Currently, microRNA (miRNA) is a prevalent topic in tumor-related research. The present study focused on the mechanisms of miR-100 in CC progression. qRT-PCR analysis revealed that the miR-100 expression was notably decreased in CC tissues. In addition, miR-100 downregulation was confirmed to be significantly related to the malignant clinicopathologic features of CC patients. Furthermore, miR-100 overexpression was also verified to significantly repress CC cell proliferation, migration and invasion abilities through modulating the AKT/mTOR signaling pathway and epithelial-to-mesenchymal transition. Bioinformatics analysis and luciferase reporter assay identified that special AT-rich sequence-binding protein 1 was a functional target for miR-100 in CC cells. Moreover, miR-100 overexpression was found to markedly repress the CC tumor growth in vivo . In conclusion, the above results revealed that miR-100 functioned as a cancer suppressor in CC progression and may provide insights into the novel therapeutic target for CC treatment., (Copyright: © Huang et al.)

Ovarian cancer (OC) is a common gynecological malignant carcinoma worldwide. Accumulating research has revealed that multiple microRNAs (miRNAs) are abnormally expressed at different levels in various malignancies, playing vital roles in tumorigenesis. This study investigated the regulatory functions and potential mechanism of miR-126 in OC proliferation, invasion and migration. It was found that miR-126 was prominently downregulated in OC. Moreover, the decrease of miR-126 promoted the aggressive phenotypes and indicated poor prognosis of OC patients. Functional assays demonstrated that restoration of miR-126 dramatically repressed OC cell proliferation, migration and invasion. Furthermore, luciferase reporter assay was conducted to verify putative binding sites of miR-126 in the epidermal growth factor-like domain 7 (EGFL7) 3 untranslated region (3'UTR), indicating that EGFL7 was a target gene of miR-126 in OC cells. It was further discovered that miR-126 exerts its function on regulating ERK/MAPK pathway and epithelial-to-mesenchymal transition (EMT) in OC cells. The above findings suggested that miR-126 served as a cancer suppressor in OC, suggesting a promising application of miR-126 in the clinical diagnosis and therapeutics of OC., (Copyright: © Zhang et al.)

River networks in subtropical agricultural hilly region become an inconvenient greenhouse gas (GHG, methane and nitrous oxide) source because of the influence of human activities, which has caused large uncertainties for refinement of national GHG inventories and their global budget. Based on field monitoring experiments at high temporal resolution, we employed regression tree and importance analysis to identify quantitatively factors that influence the diffusive flux of GHGs to provide a scientific basis for reducing GHG emissions and controlling regional carbon and nitrogen losses. The results indicate that significant spatiotemporal variation of methane (CH 4 ) nitrous oxide (N 2 O) diffusion occurs in all the four reaches (W1, W2, W3 and W4) of Tuojia river networks. Among them, W1 contributed lowest CH 4 (22.55 μg C m -2  h -1 ) and N 2 O (5.00 μg N m -2  h -1 ) diffusive flux than the other three (P < 0.05), while W4 offered highest CH 4 (166.15 μg C m -2  h -1 ) and N 2 O (30.47 μg N m -2  h -1 ) diffusive flux but with no statistically significant difference between W2 and W3 due to homogeneous extraneous nutrition loading into the two reaches. W4 also contributed largest cumulative flux of CH 4 (14.55 kg C ha -1  yr -1 ) and N 2 O (2.69 kg N ha -1  yr -1 ) in Tuojia River networks (P < 0.05). Furthermore, the regression tree and importance analysis indicate that, in the anaerobic environment, dissolved oxygen saturation controlled the production and diffusion for both CH 4 and N 2 O. The findings of this investigation highlighted that decision support tools provide an effective pathway to enhance the GHG mitigation technology research in agroecosystems and simultaneously shed light on the global campaign on refinement of national GHG inventories as well as regional nutrient management., Competing Interests: Declaration of competing interest All the authors have seen and approved the final version of this manuscript, and they are aware of and accept responsibility for the manuscript. Therefore, there is no conflict of interest to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Effectiveness of N might be modified in rice cultivation under future climate change with elevated atmospheric CO 2 concentration ([CO 2 ]). At present, limited information is available to understand how plant N uptake and N use efficiency respond to elevated [CO 2 ] and/or temperature in Chinese double rice cropping systems. A four-year field experiment was therefore conducted using open-top chambers with varying [CO 2 ] (ambient, ambient +60 μmol mol - 1 ) and varying temperature (ambient, ambient +2 °C) in Hubei Province, Central China. Compared with ambient conditions, elevated [CO 2 ] increased plant N uptake and N use efficiency, as measured by fertilizer N recovery efficiency (NRE), N agronomic efficiency (NAE), N physiological efficiency (NPE) and apparent system N use efficiency (NUE sys ), in both early rice and late rice. CO 2 enrichment tended to decrease soil mineral N concentration since more N was assimilated by plants. Elevated temperature led to lower plant N uptake and decreased NRE and NAE in early rice, due to a reduction in grain yield induced by heat injury. In contrast, warming increased plant N uptake and N use efficiency in late rice as no heat stress existed. Warming tended to increase soil mineral N concentration in early rice but had negligible effects in late rice. When elevated [CO 2 ] and temperature were combined, the positive effects of CO 2 enrichment for N utilization were able to compensate for the negative effects of warming in early rice, while the interaction was synergetic in late rice. Hence, co-elevation of [CO 2 ] and temperature led to higher N use efficiency (64.6% for NUE sys across four years) and decreased annual N surplus by 28.6-36.5 kg N ha - 1 compared with ambient conditions. Our findings confirm that CO 2 enrichment and air warming can improve N use efficiency at both crop level and system level in Chinese double rice cultivation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Climate change and anthropogenic activities have resulted in increased atmospheric methane (CH 4 ) concentration. Increased nitrogen deposition and precipitation accompanies climate warming and can change soil carbon and nitrogen dynamics and microbial processes and alter CH 4 fluxes. To quantify the sink of the vast alpine meadows of the Tibetan Plateau and to examine how precipitation addition (P), warming (W), and nitrogen addition (N) affect CH 4 fluxes in alpine meadows, we conducted continuous 3-growing season experiments in an alpine meadow using the static chamber and gas chromatograph method. Soil CH 4 samples were collected during the early, peak, and late stages of the growing season from 2015 to 2017. Our results suggested that neither P, W, nor N had an interaction effect on soil CH 4 uptake. P significantly increased and decreased the copies number of particulate methane monooxygenase alpha subunit (pmoA) and methyl-coenzyme M reductase alpha subunit (mcrA), respectively. However, P significantly decreased CH 4 uptake, particularly under the combined treatment of P and N. Compared with the control, CH 4 uptake decreased under P, N, PW, and PN by 50.64%, 6.24%, 39.37%, and 75.06%, respectively, whereas under W and WN CH 4 uptake increased by 16.19% and 7.56%, respectively. Soil CH 4 uptake was positively correlated with soil temperature and pmoA and negatively correlated with soil moisture and NH 4 + -N content. CH 4 uptake was significantly affected by the sampling period. CH 4 uptake was significantly lower rates during peak growing season compared with those during the early and late stages of the growing season. Our results suggest that, (1) CH 4 fluxes of alpine grassland ecosystems are more sensitive to P than W or N, and (2) precipitation controls CH 4 flux response to increasing nitrogen deposition in alpine meadows on the Tibetan Plateau. Therefore, future research should focus on the response and feedback of CH 4 uptake to changes in precipitation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Vegetable oils are mainly stored in the form of triacylglycerol (TAG) in oilseeds. Fatty acids (FAs), one of the building blocks for TAG assembly, are synthesized in plastids and then exported to the endoplasmic reticulum for storage oil synthesis. A recent study demonstrated that the export of FAs from plastids was mediated by a FAX (FA export) family protein. However, the significance of FAs export from plastid during seed oil accumulation has not been investigated. In this study, we found that FAX2 was highly expressed in developing Arabidopsis seeds and the expression level was consistent with FAs synthesis activity. FAX2 mutant seeds showed an approximately 18% reduction of lipid levels compared with wild-type seeds. By contrast, overexpression of FAX2 enhanced seed lipid accumulation by up to 30%. The FAs export activity of FAX2 was confirmed by yeast mutant cell complementation analysis. Our results showed that FAX2 could interact with other proteins to facilitate FAs transport. Taken together, these results indicate that FAX2-mediated FA export from plastids is important for seed oil accumulation, and that FAX2 can be used as a target gene for increasing lipid production in oilseeds., (� The Author(s) 2019. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Assessment of indirect emission factors (EF 5r ) of nitrous oxide (N 2 O) from agricultural river networks remains challenging, and results are uncertain due to limited data availability. This study compared two methods of assessing EF 5r using data from long-term observations at high temporal resolution in a typical agricultural catchment in subtropical central China. The concentration method (method 1) and the Intergovernmental Panel on Climate Change (IPCC) 2006 method (method 2) were employed to evaluate the emission factor. EF 5r estimated using method 1 (i.e., EF 5r1 ) was 0.00077 ± 0.00025 (0.00038-0.00097). EF 5r calculated using method 2 (i.e., EF 5r2 ) was lower than EF 5r1 , with a mean value of 0.00004 (0.000015-0.00012). Both EF 5r1 and EF 5r2 were significantly lower than the IPCC 2006 default value of 0.0025, suggesting that N 2 O emissions from China and world river networks may be grossly overestimated. A complex N 2 O production pathway and diffusion mechanism were responsible for the transfer of N 2 O from the sediment to river water and then to the atmosphere. These findings provide essential data for refining national greenhouse gas inventories and contribute evidence for downward revision of indirect emission factors adopted by the IPCC.

Rice is a staple food for nearly half of the world's population, but rice paddies constitute a major source of anthropogenic CH 4 emissions. Root exudates from growing rice plants are an important substrate for methane-producing microorganisms. Therefore, breeding efforts optimizing rice plant photosynthate allocation to grains, i.e., increasing harvest index (HI), are widely expected to reduce CH 4 emissions with higher yield. Here we show, by combining a series of experiments, meta-analyses and an expert survey, that the potential of CH 4 mitigation from rice paddies through HI improvement is in fact small. Whereas HI improvement reduced CH 4 emissions under continuously flooded (CF) irrigation, it did not affect CH 4 emissions in systems with intermittent irrigation (II). We estimate that future plant breeding efforts aimed at HI improvement to the theoretical maximum value will reduce CH 4 emissions in CF systems by 4.4%. However, CF systems currently make up only a small fraction of the total rice growing area (i.e., 27% of the Chinese rice paddy area). Thus, to achieve substantial CH 4 mitigation from rice agriculture, alternative plant breeding strategies may be needed, along with alternative management., (© 2018 John Wiley & Sons Ltd.)

Numerous studies have implicated tumor necrosis factor α (TNFα) in the pathogenesis of type 2 diabetes. However, the role of its primary receptor, TNF receptor 1 (TNFR1), in homeostatic regulation of glucose metabolism is still controversial. In addition to TNFα, lymphotoxin α (LTα) binds to and activates TNFR1. Thus, TNFα and LTα together are known as TNF. To delineate the role of TNF signaling in glucose homeostasis, the present study ascertained how TNF signaling deficiency affects major regulatory components of glucose homeostasis. To this end, normal diet-fed male TNFR1 deficient mice (TNFR1-/-), TNFα/LTα/LTβ triple deficient mice (TNF/LT∆3), and their littermate controls were subjected to intraperitoneal glucose tolerance test, insulin tolerance test, and oral glucose tolerance test. The present results showed that TNFR1-/- and TNF/LT∆3 mice versus their controls had comparable body weight, tolerance to intraperitoneal glucose, and sensitivity to insulin. However, their tolerance to oral glucose was significantly increased. Additionally, glucose-induced insulin secretion assessments revealed that TNFR1 or TNF/LT deficiency significantly increased oral but not intraperitoneal glucose-induced insulin secretion. Consistently, qPCR and immunohistochemistry analyses showed that TNFR1-/- and TNF/LT∆3 mice versus their controls had significantly increased ileal expression of glucagon-like peptide-1 (GLP-1), one of the primary incretins. Their oral glucose-induced secretion of GLP-1 was also significantly increased. These data collectively suggest that physiological TNF signaling regulates glucose metabolism primarily through effects on GLP-1 expression and secretion and subsequently insulin secretion.

Environmental stressors that encounter in early-life and cause abnormal fetal and/or neonatal development may increase susceptibility to non-communicable diseases such as diabetes. Maternal exposure to ambient fine particulate matter (PM 2.5 ) is associated with various fetal abnormalities, suggesting that it may program offspring's susceptibility to diabetes. In the present study, we therefore examined whether maternal exposure to diesel exhaust PM 2.5 (DEP), one of the major sources of ambient PM 2.5 in urban areas, programs adult offspring's glucose metabolism. Female C57Bl/6J mice were intratracheally instilled with DEP or vehicle throughout a 7-wk preconceptional period, gestation, and lactation, and the glucose homeostasis of their adult male offspring was assessed. Intraperitoneal glucose tolerance test (IPGTT) revealed that the maternal exposure to DEP significantly impaired adult male offspring's glucose tolerance. Unexpectedly, it did not influence their insulin sensitivity, whereas it significantly decreased their glucose-induced insulin secretion (GIIS). This deficit in insulin secretion was corroborated by their significant decrease in arginine-induced insulin secretion. Histological analysis demonstrated that the deficit in insulin secretion was accompanied by the decrease in pancreatic islet and β cell sizes. To differentiate the effects of maternal exposure to DEP before birth and during lactation, some offspring were cross-fostered once born. We did not observe any significant effect of cross-fostering on the glucose homeostasis of adult male offspring and the function and morphology of their β cells. Prenatal exposure to DEP programs the morphology and function of β cells and thus homeostatic regulation of glucose metabolism in adult male offspring.

Epidemiological studies link ambient fine particulate matter (PM2.5) pollution to abnormalities in the male reproductive system. However, few toxicological studies have investigated this potentially important adverse effect of PM2.5 pollution. Therefore, in the present study, we analyzed the effects of PM2.5 exposure on spermatogenesis and hypothalamic-pituitary-gonadal (HPG) axis in a murine model. Fourteen male C57BL/6J mice were subjected to a 4-month exposure to filtered air or concentrated ambient PM2.5 (CAP). Their sperm count, testicular histology, spermatogenic parameters, and the major components of HPG axis were assessed. Exposure to CAP significantly reduced sperm count in the epididymis. This was accompanied by Sertoli cell vacuolization, immature germ cell dislocation, and decreases in pachytene spermatocytes and round spermatids of stage VII seminiferous tubules, suggesting a marked impairment of spermatogenesis in these mice. This impairment of spermatogenesis appeared to be attributable to a suppression of HPG axis subsequent to CAP exposure-induced hypothalamic inflammation, as exposure to CAP significantly increased TNFα and IL1b mRNA levels and meanwhile decreased gonadotropin-releasing hormone mRNA expression in the hypothalamus. Moreover, CAP exposure significantly reduced circulating testosterone and follicle-stimulating hormone, testicular testosterone and mRNA expression of follicle-stimulating hormone target gene SHBG and luteinizing hormone target genes P450scc, 17βHSD, and StAR. The present data demonstrate that exposure to ambient PM2.5 impairs spermatogenesis in murine model, raising the concern over effects of ambient PM2.5 pollution on the male reproductive function.

Background: Exposure to ambient fine particulate matter (PM 2.5 ) is associated with cardiovascular mortality, but underlying pathophysiologic mechanisms are not fully understood. Hypothalamic inflammation, characterized by the activation of Inhibitor kappaB kinase 2/Nuclear factor kappaB (IKK2/NF-κB) signaling pathway, may play an important role in the pathogenesis of cardiovascular diseases. We recently demonstrated that hypothalamic inflammation is increased in mice exposed to concentrated ambient PM 2.5 (CAP)., Objectives: In the present study, we used a neuron-specific IKK2 knockout mouse model to examine the role of neural IKK2 expression and hypothalamic inflammation in the pathophysiologic effects of PM 2.5 ., Methods: We assessed inflammatory and vascular responses in Nestin-creIKK2 flox/flox (IKK2 Neu-KO ) and littermate Nestin-creIKK2 flox/+ (control) mice after 4 mo of exposure to filtered air (FA) or CAP., Results: CAP exposure was associated with significantly higher tumor necrosis factor-α (TNFα) and interleukin (IL)-6 mRNA in the hypothalamus of control mice, but not IKK2 Neu-KO mice. In addition, CAP exposure-induced increases in bronchoalveolar lavage fluid (BALF) leukocytes, pulmonary macrophage infiltration and IL-6 expression, plasma TNFα and IL-1β levels, adipose macrophage infiltration and IL-1β expression, and endothelial dysfunction were reduced or absent in IKK2 Neu-KO mice compared with controls., Conclusions: Our findings support a role of neural IKK2 in CAP exposure-induced local and systemic pro-inflammatory cytokine expression, pulmonary and adipose inflammation, and endothelial dysfunction, thus providing insight into pathophysiologic mechanisms that may mediate effects of PM 2.5 exposure. https://doi.org/10.1289/EHP2311.

The lung is constantly exposed to ambient pollutants such as ambient fine particulate matter (PM2.5), making it one of the most frequent locations of inflammation in the body. Given the establishment of crucial role of inflammation in the pathogenesis of cardiometabolic diseases, pulmonary inflammation is thus widely believed to be an important risk factor for cardiometabolic diseases. However, the causality between them has not yet been well established. To determine if pulmonary inflammation is sufficient to cause adverse cardiometabolic effects, SFTPC-rtTA+/-tetO-cre+/-pROSA-inhibitor κB kinase 2(IKK2)ca+/- (LungIKK2ca) and littermate SFTPC-rtTA+/-tetO-cre-/-pROSA-IKK2ca+/- wildtype (WT) mice were fed with doxycycline diet to induce constitutively active Ikk2 (Ikk2ca) overexpression in the lung and their pulmonary, systemic, adipose, and hypothalamic inflammations, vascular function, and glucose homeostasis were assessed. Feeding with doxycycline diet resulted in IKK2ca overexpression in the lungs of LungIKK2ca but not WT mice. This induction of IKK2ca was accompanied by marked pulmonary inflammation as evidenced by significant increases in bronchoalveolar lavage fluid leukocytes, pulmonary macrophage infiltration, and pulmonary mRNA expression of tumor necrosis factor α (Tnfα) and interleukin-6 (Il-6). This pulmonary inflammation due to lung-specific overexpression of IKK2ca was sufficient to increase circulating TNFα and IL-6 levels, adipose expression of Tnfα and Il-6 mRNA, aortic endothelial dysfunction, and systemic insulin resistance. Unexpectedly, no significant alteration in hypothalamic expression of Tnfα and Il-6 mRNA and glucose intolerance were observed in these mice. Pulmonary inflammation is sufficient to induce systemic inflammation, endothelial dysfunction, and insulin resistance, but not hypothalamic inflammation and glucose intolerance., (© The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Exposure to ambient fine particulate matter (PM 2.5 ) is associated with increased cardiometabolic morbidity and mortality. This is widely believed to be attributable to PM 2.5 exposure-induced pulmonary and subsequent systemic inflammation. Tumor necrosis factor alpha (TNFα), lymphotoxin α (LTα), and lymphotoxin β (LTβ) are three homologous pro-inflammatory cytokines, each with both unique and redundant activities in inflammation. Their role in PM 2.5 exposure-induced inflammation and adverse cardiometabolic effects has to be determined., Methods and Results: LTα/TNFα/LTβ triple-knockout (TNF/LT KO) and wildtype (WT) mice were exposed to concentrated ambient PM 2.5 (CAP) for 5 months. Lung pathological analysis revealed that TNF/LT deficiency reduced CAP exposure-induced pulmonary inflammation. However, glucose homeostasis assessments showed that TNF/LT deficiency significantly aggravated CAP exposure-induced glucose intolerance and insulin resistance. Consistent with glucose homeostasis assessments, CAP exposure significantly increased the body weight and adiposity of TNF/LT KO but not WT mice. In contrast to its body weight effects, CAP exposure reduced food intake of WT but not TNF/LT KO mice. On the other hand, CAP exposure induced marked fat droplet accumulation in brown adipose tissues of WT mice and significantly decreased their uncoupling protein 1 (UCP1) expression, and these effects were markedly exacerbated in TNF/LT KO mice., Conclusion: The present study suggests that TNF/LT deficiency influences PM 2.5 exposure-induced response of energy metabolism through alterations in both food intake and energy expenditure., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Many diseases including obesity may originate through alterations in the early-life environment that interrupts fetal development. Increasing evidence has shown that exposure to ambient fine particles (PM 2.5 ) is associated with abnormal fetal development. However, its long-term metabolic effects on offspring have not been systematically investigated., Results: To determine if maternal exposure to PM 2.5 programs offspring obesity, female C57Bl/6j mice were exposed to filtered air (FA) or concentrated ambient PM 2.5 (CAP) during pre-conception, pregnancy, and lactation, and the developmental and metabolic responses of offspring were assessed. The growth trajectory of offspring revealed that maternal exposure to CAP significantly decreased offspring birth weight but increased body weight of adult male but not female offspring, and the latter was expressed as increased adiposity. These adult male offspring had increased food intake, but were sensitive to exogenous leptin. Their hypothalamic expression of Socs3 and Pomc, two target genes of leptin, was not changed, and the hypothalamic expression of NPY, an orexigenic peptide that is inhibited by leptin, was significantly increased. These decreases in central anorexigenic signaling were accompanied by reduced plasma leptin and its expression in adipose tissues, the primary source of circulating leptin. In contrast, maternal exposure did not significantly change any of these indexes in adult female offspring. Pyrosequencing demonstrated that the leptin promoter methylation of adipocytes was significantly increased in CAP-exposed male but not female offspring., Conclusions: Our data indicate that maternal exposure to ambient PM 2.5 programs obesity in male offspring probably through alterations in the methylation of the promoter region of the leptin gene.

Background: Obesity is one of the leading threats to global public health. It is consequent to abnormal energy metabolism. Currently, it has been well established that maternal exposure to environmental stressors that cause inappropriate fetal development may have long-term adverse effects on offspring energy metabolism in an exposure timing-dependent manner, known as developmental programming of health and diseases paradigm. Rapidly increasing evidence has indicated that maternal exposure to ambient fine particles (PM 2.5 ) correlates to abnormal fetal development. In the present study, we therefore assessed whether maternal exposure to diesel exhaust PM 2.5 (DEP), the major component of ambient PM 2.5 in urban areas, programs offspring energy metabolism, and further examined how the timing of exposure impacts this programming., Results: The growth trajectory of offspring shows that although prenatal maternal exposure to DEP did not impact the birth weight of offspring, it significantly decreased offspring body weight from postnatal week 2 until the end of observation. This weight loss effect of prenatal maternal exposure to DEP coincided with decreased food intake but not alteration in brown adipose tissue (BAT) morphology. The hypophagic effect of prenatal maternal exposure to DEP was in concord with decreased hypothalamic expression of an orexigenic peptide NPY, suggesting that the prenatal maternal exposure to DEP impacts offspring energy balance primarily through programming of food intake. Paradoxically, the reduced body weight resulted from prenatal maternal exposure to DEP was accompanied by increased mass of epididymal adipose tissue, which was due to hyperplasia as morphological analysis did not observe any hypertrophy. In direct contrast, the postnatal mothering by DEP-exposed dams increased offspring body weight during lactation and adulthood, paralleled by markedly increased fat accumulation and decreased UCP1 expression in BAT but not alteration in food intake. The weight gain induced by postnatal mothering by DEP-exposed dams was also expressed as an increased adiposity. But it concurred with a marked hypertrophy of adipocytes., Conclusion: Prenatal and postnatal mothering by DEP-exposed dams differentially program offspring energy metabolism, underscoring consideration of the exposure timing when examining the adverse effects of maternal exposure to ambient PM 2.5 .

To evaluate long-term effect of biochar application on yield-scaled greenhouse gas emissions (YSGE) in a paddy rice cropping system, a 4-year field experiment by static chamber - gas chromatograph method was conducted in South China. Principal component analysis and terminal restriction fragment length polymorphism (T-RFLP) and real-time qPCR was used to unravel the microbial mechanisms of biochar addition. Six treatments were included: control (CK), application of 5tha(-1) biochar (BC1), application of 10tha(-1) biochar (BC2), application of 10tha(-1) biochar (BC3), rice straw return at 2400kgha(-1)(RS) and inoculated rice straw return at 2400kgha(-1)(RI). The results indicated that biochar amendment significantly decreased methane (CH4) and gross greenhouse gas (GHG) emissions. This may primarily be ascribed to the stimulated biodiversity and abundance of methanotrophic microbes, increased soil pH and improved aeration by reducing bulk density after biochar incorporation. Compared with CK, RS and RI, 26.18%, 70.02%, 66.47% of CH4 flux and 26.14%, 70.16%, 66.46% of gross GHG emissions were reduced by biochar (mean of three biochar treatments), respectively. Furthermore, biochar significantly increased harvest index of double rice production (p<0.05). In comparison with CK, RS and RI, 29.14%, 68.04%, 62.28% of YSGE was reduced by biochar, respectively, and the highest biochar addition rate (20tha(-1)) contributed most to the mitigation of GHG emissions (36.24% decrease compared to CK) and improvement of rice yield (7.65% increase compared to CK). Results of our study suggested that long-term application of biochar should be the potential way to mitigate GHGs emissions and simultaneously improve rice productivity in the paddy rice system., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Changes in climate have caused impacts on ecosystems on all continents scale, and climate change is also projected to be a stressor on most ecosystems even at the rate of low- to medium-range warming scenarios. Alpine ecosystem in the Qinghai-Tibetan Plateau is vulnerable to climate change. To quantify the climate change impacts on alpine ecosystems, we simulated the vegetation distribution and net primary production in the Qinghai-Tibetan Plateau for three future periods (2020s, 2050s and 2080s) using climate projection for RCPs (Representative Concentration Pathways) RCP4.5 and RCP8.5 scenarios. The modified Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ model) was parameter and test to make it applicable to the Qinghai-Tibetan Plateau. Climate projections that were applied to LPJ model in the Qinghai-Tibetan Plateau showed trends toward warmer and wetter conditions. Results based on climate projections indicated changes from 1.3°C to 4.2°C in annual temperature and changes from 2% to 5% in annual precipitation. The main impacts on vegetation distribution was increase in the area of forests and shrubs, decrease in alpine meadows which mainly replaced by shrubs which dominated the eastern plateau, and expanding in alpine steppes to the northwest dominated the western and northern plateau. The NPP was projected to increase by 79% and 134% under the RCP4.5 and RCP8.5. The projected NPP generally increased about 200gC·m(-2)·yr(-1) in most parts of the plateau with a gradual increase from the eastern to the western region of the Qinghai-Tibetan Plateau at the end of this century., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Detection and identification of the impacts of climate change on ecosystems have been core issues in climate change research in recent years. In this study, we compared average annual values of the normalized difference vegetation index (NDVI) with theoretical net primary productivity (NPP) values based on temperature and precipitation to determine the effect of historic climate change on global grassland productivity from 1982 to 2011. Comparison of trends in actual productivity (NDVI) with climate-induced potential productivity showed that the trends in average productivity in nearly 40% of global grassland areas have been significantly affected by climate change. The contribution of climate change to variability in grassland productivity was 15.2-71.2% during 1982-2011. Climate change contributed significantly to long-term trends in grassland productivity mainly in North America, central Eurasia, central Africa, and Oceania; these regions will be more sensitive to future climate change impacts. The impacts of climate change on variability in grassland productivity were greater in the Western Hemisphere than the Eastern Hemisphere. Confirmation of the observed trends requires long-term controlled experiments and multi-model ensembles to reduce uncertainties and explain mechanisms.

High chilling-susceptibility is becoming the bottleneck for cultivation and commercialization of Jatropha curcas L. For insights to chilling resistance ability of this plant species, a cold response transcription factor, JcCBF2, was cloned and studied. It codes a 26 kDa protein, which contains all conserved motifs unique to the C-repeat binding factor (CBF) family and has high similarity to CBFs of Ricinus communis and Populus. Its transcripts express specifically in leaves of Jatropha at cold temperature. After transmitting the report vector, 35S::JcCBF2-GFP, into Arabidopsis thaliana, JcCBF2 protein is main detected in cell nucleus, being consistent to the nuclear orientation signal in its N-terminal. Compared to the control Arabidopsis, the frozen leaves of JcCBF2-overexpressed seedlings grow stronger with less malondialdehyde, smaller leaf conductivity and activer superoxide dismutase, showing their higher freezing tolerance. RT-PCR tests revealed that JcCBF2 functioned mainly at the early stage (0-6 h) of resistance events in Arabidopsis, and its transcripts reduced after 6 h. In addition, JcCBF2 could quickly regulate transcripts of some cold-responsive (COR) genes such as RD29A, COR105A and COR6.6, also during the early stage of frozen treatment. This study not only proves the chilling resistance roles of JcCBF2, but also presents a candidate gene engineering for improvement of chilling tolerance in J. curcas.

This retrospective study aimed to investigate blood pressure variability (BPV), morning systolic blood pressure surge (MBPS), and the associated factors in 513 elderly (65 years and older) and 188 younger (younger than 65 years) hypertensive Chinese patients who had ambulatory blood pressure monitoring (ABPM) at our hospital from January 1, 2002, to December 31, 2010. The MBPS was lower in the younger patients compared with the elderly patients, and it was highest in the 75 years and older and younger than 80 group (29.0±13.4 mm Hg). Compared with other groups, the 80 years and older group had a significant increase in BPV (P<.05). Multiple linear regression analysis showed that body mass index (BMI; P<.01), up to 50 years of smoking (P≤.03), and circadian blood pressure variation (P<.01) were factors associated with MPBS. In summary, systolic BPV and MBPS were increased in elderly Chinese hypertensive patients, and the MBPS was associated with BMI, years of smoking, and circadian blood pressure variation., (©2014 Wiley Periodicals, Inc.)

Jatropha curcas, a biodiesel plant with a short life cycle, has great potentials to be a new model woody plant. In this study, we found a plant-specific transcription factor JcNAC1, an intriguing regulator modulating plant responses to abiotic stresses and pathogen infection. Expression of JcNAC1 was strongly increased when plants were treated with abscisic acid, salt and polyethylene glycol, and was decreased with salicylic acid, ethylene, and pathogens. Overexpressing JcNAC1 plants showed enhanced tolerance to drought and increased susceptibility to pathogens. Furthermore, over-expression of JcNAC1 in plants also resulted in the expression changes of some stress-related maker genes including curcin-L, which is a special stress-inducible ribosome-inactivating protein gene in J. curcas. These results indicate that JcNAC1 is responsible for stress responses in J. curcas.

A PAL gene designated as JcPAL1 was cloned from J. curcas L. The full-length is 2336 bp in size with one intron and two exons, encoding a polypeptide of 713 amino acids. Its 5'-upstream region is rich in putative cis-elements including not only PAL typical TATA box, L-box and transcriptional initiation site (TIS) but also light responding motifs. Expression pattern analysis indicated that JcPAL1 were expressed in all tissues, most highly in flowers. When Treated with ABA, GA3, high and low temperature, expression of JcPAL1 were induced. Recombinant JcPAL1 has a pH optimum at 8.7 and a temperature optimum at 60°C in 100 mM Tris-HCl buffer. The Km and Kcat values are 0.125 mM and 1.73 S(-1) for L: -phenylalanine, and 1.312 mM and 0.109 S(-1) for L: -tyrosine, respectively. These findings suggested that JcPAL1 might involve in the J. curcas responding to various stresses and L: -Phe should be its true physiological substrate. This study is essential prior to uncover whether and how the PAL initiated phenylpropanoid metabolic networks functioning in the defense responses of J. curcas.

A cDNA encoding translationally controlled tumor protein (TCTP) of Jatropha curcas L., JcTCTP, was isolated from an endosperm cDNA library. JcTCTP consisted of a 5' untranslated region (UTR) of 526 bp, a 3' UTR of 377 bp and an open reading frame (ORF) of 507 bp, encoding a protein of 168 amino acid residues, which contained two signature sequences of TCTP family. Its deduced amino acid sequence was similar to the other known plants TCTPs in a range of 77.4-92.3%. Expression of JcTCTP was the highest in the stem, endosperm at embryo formation stage and embryo of J. curcas tissues, and the lowest in the endosperm at seminal leaf embryo stage and flower, demonstrating a pattern of temporal and spatial specific expression.

A cDNA clone designated arf1 was isolated from a physic nut (Jatropha curcas L.) endosperm cDNA library which encodes a small GTP-binding protein and has significant homology to ADP-ribosylation factors (ARF) in plants, animals and microbes. The cDNA contains an open reading frame that encodes a polypeptide of 181 amino acids with a calculated molecular mass of 20.7 kDa. The deduced amino acid sequence showed high homology to known ARFs from other organisms. The products of the arf1 obtained by overexpression in E. coli revealed the specific binding activity toward GTP. The expression of arf1 was observed in flowers, roots, stems and leaves as analyzed by RT-PCR, and its transcriptional level was highest in flowers. In particular, the accumulation of arf1 transcripts was different under various environmental stresses in seedlings. The results suggest that arf1 plays distinct physiological roles in Jatropha curcas cells.

To date, two types of ribosome-inactivating proteins (RIPs) have been found in Jatropha curcas. One is curcin, which has been isolated from the endosperm, and the other is curcin-L, which is expressed in leaves upon stress treatment. Phylogenetic analysis of the predicted amino acid sequences of the RIPs in plants revealed that these belong to a major subfamily and are close to trichosanthin (TCS). Studies on the mRNA and protein levels showed that both curcin and curcin-L have an organ-specific expression pattern. Curcin is only expressed and accumulated in the endosperm; its expression begins in the globular embryo period and peaks during the mature embryo period. In contrast, curcin-L is only expressed in the leaves, but its expression is induced by certain conditions such as treatment with phytohormones or polyethylene glycol, exposure to high and low temperatures, and fungal infection. Analysis of the 5' flanking regions of curcin and curcin-L revealed that the 5' flanking region of curcin-L has three major inserted fragments, which are not present in the corresponding region of curcin. Comparison of characteristic cis-elements suggests the presence of several motifs that are involved in the endosperm-specific expression in the 5' flanking region of curcin, while in curcin-L some stress- and defense-responsive motifs are found to be mainly located in the three inserted fragments. Comparison of the antifungal activity of the two RIPs showed that the one of curcin-L is higher than that of curcin. Differences in the expression and activity of curcin and curcin-L suggest that these two RIPs have different functions.

Ribosome-inactivating proteins (RIPs) represent a type of protein that universally inactivates the ribosome thus inhibiting protein biosynthesis. Curcin-L was a type I RIP found in Jatropha curcas L.. Its expression could be activated in leaves by treatments with abscisic acid, salicylic acid, polyethylene glycol, temperature 4, 45 degrees C and ultraviolet light. A 654 bp fragment of a 5' flanking region preceding the curcin-L gene, designated CP2, was cloned from the J. curcas genome and its expression pattern was studied via the expression of the beta-glucuronidase (GUS) gene in transgenic tobacco. Analysis of GUS activities showed that the CP2 was leaf specific, and was able to drive the expression of the reporter gene under stress-induction conditions. Analysis of a series of 5'-deletions of the CP2 suggested that several promoter motifs were necessary to respond to environmental stresses.