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241.
Huai Chen Qiuan Zhu Changhui Peng Ning Wu Yanfen Wang Xiuqing Fang Yongheng Gao Dan Zhu Gang Yang Jianqing Tian Xiaoming Kang Shilong Piao Hua Ouyang Wenhua Xiang Zhibin Luo Hong Jiang Xingzhang Song Yao Zhang Guirui Yu Xinquan Zhao Peng Gong Tandong Yao Jianghua Wu 《Global Change Biology》2013,19(10):2940-2955
With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles. 相似文献
242.
Yanchang Luo Zhongchao Yin 《Molecular breeding : new strategies in plant improvement》2013,32(3):709-721
Rice is a staple food crop for more than half of the world’s population. However, rice production is affected by many types of abiotic and biotic stress. Genetic breeding by utilizing natural resistance or tolerance genes is the most economic and efficient way to combat or adapt to these stresses. Khao Dawk Mali 105 (KDML 105) is an elite cultivar of aromatic rice mainly grown in Thailand. However, the production of KDML 105 is affected by lodging problems due to its tall plant type, regular flash floods or short-term submergence during the monsoon season, and diseases such as blast and bacterial blight. Here we report the pyramiding of semi-dwarf gene sd1, submergence tolerance gene Sub1A, blast resistance gene Pi9 and bacterial blight resistance genes Xa21 and Xa27 in KDML 105 by marker-assisted selection. The improved line, designated T5105, has a semi-dwarf phenotype with improved lodging resistance and a greater harvest index. T5105 survives after 2 weeks of complete submergence without significant loss of viability. T5105 confers high resistance to all five Magnaporthe oryzae isolates tested and provides resistance or moderate resistance to 25 of the 27 Xanthomonas oryzae pv. oryzae strains tested. In addition, T5105 produced higher yield than KDML 105 in two field trials and retains similar good grain quality to KDML 105. The development of T5105 provides a new line to boost the production of high-quality aromatic rice in tropical regions. 相似文献
243.
Loai M. Alnemer Raed I. Seetan Filippo M. Bassi Charith Chitraranjan Adam Helsene Paul Loree Steve Bou Goshn Yong Q. Gu Ming-Cheng Luo M. Javed Iqbal Gerard R. Lazo Anne M. Denton Shahryar F. Kianian 《Functional & integrative genomics》2013,13(1):11-17
In the course of evolution, the genomes of grasses have maintained an observable degree of gene order conservation. The information available for already sequenced genomes can be used to predict the gene order of nonsequenced species by means of comparative colinearity studies. The “Wheat Zapper” application presented here performs on-demand colinearity analysis between wheat, rice, Sorghum, and Brachypodium in a simple, time efficient, and flexible manner. This application was specifically designed to provide plant scientists with a set of tools, comprising not only synteny inference, but also automated primer design, intron/exon boundaries prediction, visual representation using the graphic tool Circos 0.53, and the possibility of downloading FASTA sequences for downstream applications. Quality of the “Wheat Zapper” prediction was confirmed against the genome of maize, with good correlation (r?>?0.83) observed between the gene order predicted on the basis of synteny and their actual position on the genome. Further, the accuracy of “Wheat Zapper” was calculated at 0.65 considering the “Genome Zipper” application as the “gold” standard. The differences between these two tools are amply discussed, making the point that “Wheat Zapper” is an accurate and reliable on-demand tool that is sure to benefit the cereal scientific community. The Wheat Zapper is available at http://wge.ndsu.nodak.edu/wheatzapper/. 相似文献
244.
Yichi Zhang Yan Luo Kaijing Li Min Zhang Bing Huang Yuting Peng Wenchong Wang Weihua Li Yizhi Liu 《Cytotherapy》2013,15(11):1416-1425
Background aimsRecent advances in stem cell research have raised the possibility of stem cells repairing or replacing retinal photoreceptor cells that are either dysfunctional or lost in many retinal diseases. Various types of stem cells have been used to replace retinal photoreceptor cells. Recently, peripheral blood stem cells, a small proportion of pluripotent stem cells, have been reported to mainly exist in the peripheral blood mononuclear cells (PBMCs).MethodsIn this study, the effects of pre-induced adult human PBMCs (hPBMCs) on the degenerative retinas of rd1 mice were investigated. Freshly isolated adult hPBMCs were pre-induced with the use of the conditioned medium of rat retinas for 4 days and were then labeled with chloromethyl-benzamidodialkylcarbocyanine (CM-DiI) and then transplanted into the subretinal space of the right eye of rd1 mice through a trans-scleral approach. The right eyes were collected 30 days after transplantation. The survival and migration of the transplanted cells in host retinas were investigated by whole-mount retinas, retinal frozen sections and immunofluorescent staining.ResultsAfter subretinal transplantation, pre-induced hPBMCs were able to survive and widely migrate into the retinas of rd1 mice. A few CM-DiI–labeled cells migrated into the inner nuclear layer and the retinal ganglion cell layer. Some transplanted cells in the subretinal space of rd1 host mice expressed the human photoreceptor–specific marker rhodopsin.ConclusionsThis study suggests that pre-induced hPBMCs may be a potential cell source of cell replacement therapy for retinal degenerative diseases. 相似文献
245.
Lei Wang Jie Zheng Yanzhong Luo Tao Xu Qiuxue Zhang Lan Zhang Miaoyun Xu Jianmin Wan Ming‐Bo Wang Chunyi Zhang Yunliu Fan 《Plant biotechnology journal》2013,11(8):997-1005
Long hairpin RNA (hpRNA) transgenes are a powerful tool for gene function studies in plants, but a genomewide RNAi mutant library using hpRNA transgenes has not been reported for plants. Here, we report the construction of a hpRNA library for the genomewide identification of gene function in rice using an improved rolling circle amplification‐mediated hpRNA (RMHR) method. Transformation of rice with the library resulted in thousands of transgenic lines containing hpRNAs targeting genes of various function. The target mRNA was down‐regulated in the hpRNA lines, and this was correlated with the accumulation of siRNAs corresponding to the double‐stranded arms of the hpRNA. Multiple members of a gene family were simultaneously silenced by hpRNAs derived from a single member, but the degree of such cross‐silencing depended on the level of sequence homology between the members as well as the abundance of matching siRNAs. The silencing of key genes tended to cause a severe phenotype, but these transgenic lines usually survived in the field long enough for phenotypic and molecular analyses to be conducted. Deep sequencing analysis of small RNAs showed that the hpRNA‐derived siRNAs were characteristic of Argonaute‐binding small RNAs. Our results indicate that RNAi mutant library is a high‐efficient approach for genomewide gene identification in plants. 相似文献
246.
247.
Plant invasion is one of the major threats to natural ecosystems. Phenotypic plasticity is considered to be important for promoting plant invasiveness. High tolerance of stress can also increase survival of invasive plants in adverse habitats. Limited growth and conservation of carbohydrate are considered to increase tolerance of flooding in plants. However, few studies have examined whether invasive species shows a higher phenotypic plasticity in response to waterlogging or a higher tolerance of waterlogging (lower plasticity) than native species. We conducted a greenhouse experiment to compare the growth and morphological and physiological responses to waterlogging of the invasive, clonal, wetland species Alternanthera philoxeroides with those of its co-occurring, native, congeneric, clonal species Alternanthera sessilis. Plants of A. philoxeroides and A. sessilis were subjected to three treatments (control, 0 and 60 cm waterlogging). Both A. philoxeroides and A. sessilis survived all treatments. Overall growth was lower in A. philoxeroides than in A. sessilis, but waterlogging negatively affected the growth of A. philoxeroides less strongly than that of A. sessilis. Alternanthera philoxeroides thus showed less sensitivity of growth traits (lower plasticity) and higher waterlogging tolerance. Moreover, the photosynthetic capacity of A. philoxeroides was higher than that of A. sessilis during waterlogging. Alternanthera philoxeroides also had higher total non-structural and non-soluble carbohydrate concentrations than A. sessilis at the end of treatments. Our results suggest that higher tolerance to waterlogging and higher photosynthetic capacity may partly explain the invasion success of A. philoxeroides in wetlands. 相似文献
248.
249.
Fei Zhao Weiwei Huang Tamgue Ousman Bin Zhang Yangyang Han Daguia Zambe John Clotaire Chen Wang Huanhuan Chang Huanan Luo Xiaoyong Ren Ming Lei 《PloS one》2013,8(11)
Triptolide, an active compound extracted from Chinese herb Leigongteng (Tripterygium wilfordii Hook F.), shows a broad-spectrum of anticancer activity through its cytotoxicity. However, the efficacy of triptolide on laryngocarcinoma rarely been evaluated, and the mechanism by which triptolide-induced cellular apoptosis is still not well understood. In this study, we found that triptolide significantly inhibited the laryngocarcinoma HEp-2 cells proliferation, migration and survivability. Triptolide induces HEp-2 cell cycle arrest at the G1 phase and apoptosis through intrinsic and extrinsic pathways since both caspase-8 and -9 are activated. Moreover, triptolide enhances p53 expression by increasing its stability via down-regulation of E6 and E6AP. Increased p53 transactivates down-stream target genes to initiate apoptosis. In addition, we found that short time treatment with triptolide induced DNA damage, which was consistent with the increase in p53. Furthermore, the cytotoxicity of triptolide is decreased by p53 knockdown or use of caspases inhibitor. In conclusion, our results demonstrated that triptolide inhibits cell proliferation and induces apoptosis in laryngocarcinoma cells by enhancing p53 expression and activating p53 functions through induction of DNA damage and suppression of E6 mediated p53 degradation. These studies indicate that triptolide is a potential anti-laryngocarcinoma drug. 相似文献
250.
Xing-yu Feng Wei Wang Guang-yu Luo Jing Wu Zhi-wei Zhou Wei Li Xiao-wei Sun Yuan-fang Li Da-zhi Xu Yuan-xiang Guan Shi Chen You-qing Zhan Xiao-shi Zhang Guo-liang Xu Rong Zhang Ying-bo Chen 《PloS one》2013,8(11)