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排序方式: 共有2313条查询结果,搜索用时 187 毫秒
61.
Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments 总被引:1,自引:0,他引:1
62.
Two amino acids near the N‐terminus of Cucumber mosaic virus 2b play critical roles in the suppression of RNA silencing and viral infectivity 下载免费PDF全文
Kai Dong Ying Wang Zhen Zhang Long‐Xiang Chai Xin Tong Jin Xu Dawei Li Xian‐Bing Wang 《Molecular Plant Pathology》2016,17(2):173-183
Cucumber mosaic virus (CMV) 2b suppresses RNA silencing primarily through the binding of double‐stranded RNA (dsRNA) of varying sizes. However, the biologically active form of 2b remains elusive. Here, we demonstrate that the single and double alanine substitution mutants in the N‐terminal 15th leucine and 18th methionine of CMV 2b exhibit drastically attenuated virulence in wild‐type plants, but are efficiently rescued in mutant plants defective in RNA‐dependent RNA polymerase 6 (RDR6) and Dicer‐like 4 (DCL4). Moreover, the transgenic plants of 2b, but not 2blm (L15A/M18A), rescue the high infectivity of CMV‐Δ2b through the suppression of antiviral silencing. L15A, M18A or both weaken 2b suppressor activity on local and systemic transgene silencing. In contrast with the high affinity of 2b to short and long dsRNAs, 2blm is significantly compromised in 21‐bp duplex small interfering RNA (siRNA) binding ability, but maintains a strong affinity for long dsRNAs. In cross‐linking assays, 2b can form dimers, tetramers and oligomers after treatment with glutaraldehyde, whereas 2blm only forms dimers, rather than tetramers and oligomers, in vitro. Together, these findings suggest that L15 and M18 of CMV 2b are required for high affinity to ds‐siRNAs and oligomerization activity, which are essential for the suppression activity of 2b on antiviral silencing. 相似文献
63.
Dong Lin Yubo Chai Reza Izadpanah Stephen E. Braun 《Cell cycle (Georgetown, Tex.)》2016,15(18):2414-2419
Natriuretic peptide receptor 3 (NPR3) is a clearance receptor by binding and internalizing natriuretic peptides (NPs) for ultimate degradation. Patients with cardiac failure show elevated NPs. NPs are linked to poor long-term survival because of their apoptotic effects. However, the underling mechanisms have not been identified yet. Here we report the role of NPR3 in anti-apoptosis via the breast cancer type 1 susceptibility protein (BRCA1) and tumor necrosis factor α (TNF-α ). To demonstrate a role for NPR3 in apoptosis, stable H9C2 cardiomyocyte cell lines using shRNA to knockdown NPR3 were generated. The activities of caspase-3, 8, and 9 were significantly increased in NPR3 knockdown H9C2 cardiomyocytes. Knockdown of NPR3 increased the expression of BRCA1. Also NPR3 knockdown remarkably increased the activity of cAMP response element-binding protein (CREB), a positive regulatory element for BRCA1 expression. BRCA1 showed dispersed nuclear localization in non-cardiomyocytes while predominantly cytoplasmic localization in H9C2 cells. Meanwhile, NPR3 knockdown significantly increased TNF-α gene expression. These data show that NPR3 knockdown in H9C2 cells triggered both extrinsic and intrinsic apoptotic pathways. NPR3 protects cardiomyocytes from apoptosis through inhibition of cytosolic BRCA1 and TNF-α, which are regulators of apoptosis. Our studies demonstrate anti-apoptosis role of NPR3 in protecting cardiomyocytes and establish the first molecular link between NP system and programmed cell death. 相似文献
64.
Huan Zhang Shanshan Zhu Tianzhen Liu Chunming Wang Zhijun Cheng Xin Zhang Liping Chen Peike Sheng Maohong Cai Chaonan Li Jiachang Wang Zhe Zhang Juntao Chai Liang Zhou Cailin Lei Xiuping Guo Jiulin Wang Jie Wang Ling Jiang Chuanyin Wu Jianmin Wan 《Plant biotechnology journal》2019,17(2):531-539
Heading date is an important agronomic trait affecting crop yield. The GRAS protein family is a plant‐specific super family extensively involved in plant growth and signal transduction. However, GRAS proteins are rarely reported have a role in regulating rice heading date. Here, we report a GRAS protein DHD1 (Delayed Heading Date1) delays heading and enhances yield in rice. Biochemical assays showed DHD1 physically interacts with OsHAP5C/D both in vitro and in vivo. DHD1 and OsHAP5C/D located in the nucleus and showed that rhythmic expression. Both DHD1 and OsHAP5C/D affect heading date by regulating expression of Ehd1. We propose that DHD1 interacts with OsHAP5C/D to delay heading date by inhibiting expression of Ehd1. 相似文献
65.
Chenqiao Zhu Xiongjie Zheng Yue Huang Junli Ye Peng Chen Chenglei Zhang Fei Zhao Zongzhou Xie Siqi Zhang Nan Wang Hang Li Lun Wang Xiaomei Tang Lijun Chai Qiang Xu Xiuxin Deng 《Plant biotechnology journal》2019,17(11):2199-2210
Hongkong kumquat (Fortunella hindsii) is a wild citrus species characterized by dwarf plant height and early flowering. Here, we identified the monoembryonic F. hindsii (designated as ‘Mini‐Citrus’) for the first time and constructed its selfing lines. This germplasm constitutes an ideal model for the genetic and functional genomics studies of citrus, which have been severely hindered by the long juvenility and inherent apomixes of citrus. F. hindsii showed a very short juvenile period (~8 months) and stable monoembryonic phenotype under cultivation. We report the first de novo assembled 373.6 Mb genome sequences (Contig‐N50 2.2 Mb and Scaffold‐N50 5.2 Mb) for F. hindsii. In total, 32 257 protein‐coding genes were annotated, 96.9% of which had homologues in other eight Citrinae species. The phylogenomic analysis revealed a close relationship of F. hindsii with cultivated citrus varieties, especially with mandarin. Furthermore, the CRISPR/Cas9 system was demonstrated to be an efficient strategy to generate target mutagenesis on F. hindsii. The modifications of target genes in the CRISPR‐modified F. hindsii were predominantly 1‐bp insertions or small deletions. This genetic transformation system based on F. hindsii could shorten the whole process from explant to T1 mutant to about 15 months. Overall, due to its short juvenility, monoembryony, close genetic background to cultivated citrus and applicability of CRISPR, F. hindsii shows unprecedented potentials to be used as a model species for citrus research. 相似文献
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68.
Ai Chenbing Yan Zhang Chai Hongsheng Gu Tianyuan Wang Junjun Chai Liyuan Qiu Guanzhou Zeng Weimin 《Journal of industrial microbiology & biotechnology》2019,46(8):1113-1127
Journal of Industrial Microbiology & Biotechnology - Extremely thermoacidophilic Crenarchaeota belonging to the order Sulfolobales, such as Metallosphaera sedula, are metabolically versatile... 相似文献
69.
An analysis of intraoperative blood transfusion of cardiac surgery in one hospital from 2014 to 2016 下载免费PDF全文
Sihua Yi Cuicui Chai Jing Lin Hongliang Zhang Qiangjun Luo Han Wang Jiangbo Chen Dan Li 《Asia-Pacific Journal of Blood Types and Genes》2019,3(2):121-124
To investigate the usage of blood componentsfor cardiac surgery inthe First Hospital of Lanzhou University, data from January 2014 to December 2016 were collected for analysis, including the number of cardiac surgeries and blood transfusions. There were 1 589 males and 1 076 females, aged from 1 to 73 years, with an average age of (53.97 ± 11.33) years, in this study. The results showed that the rate of blood-free surgery in the hospital increased year by year,while the proportion of blood-used operation to total operations decreased every year. The ratio of plasma and platelets used in cardiac surgery decreased, while the cryoprecipitate ratio used in cardiac surgery increased. This study indicates that the transfusion medical level in cardiac surgery is improved continuously, and that the infusion of blood components has become more secure, efficient and rational. 相似文献
70.
Qiu Fengti Xing Sinian Xue Chenxiao Liu Jinxing Chen Kunling Chai Tuanyao Gao Caixia 《中国科学:生命科学英文版》2022,65(4):731-738
Science China Life Sciences - Genome editing is an unprecedented technological breakthrough but low plant regeneration frequencies and genotype dependence hinder its implementation for crop... 相似文献