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991.
Virologica Sinica - 3h-31 of Heliothis virescens ascovirus 3h (HvAV-3h) is a highly conserved gene of ascoviruses. As an early gene of HvAV-3h, 3h-31 codes for a non-structural protein (3H-31) of... 相似文献
992.
Wan Qiangyou Kong Deping Liu Qian Guo Shumin Wang Chenchen Zhao Yan Ke Zun-Ji Yu Ying 《中国科学:生命科学英文版》2021,64(7):1068-1076
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit prostaglandin (PG) formation by targeting cyclooxygenase (COX) 1 and 2.Long-term use of NSAIDs that selectively inhibit COX2 increases the risk for thrombotic events,cardiac failure,and hypertension.However,the underlying mechanisms remain unclear.In this study,COX1- and COX2-deficient rats were created via Cas9/RNA-mediated gene targeting.DNA genotyping and Western blot analysis confirmed successful generation of COX1~(-/-)and COX2~(-/-)rats.Adult COX1~(-/-)rats grew normally,while more than 70%of COX2~(-/-)rats after wean died within 2 months.Echocardiography showed markedly reduced left ventricular ejection fraction and fractional shortening in adult COX2~(-/-)rats compared to those in wildtype (WT) controls.Histological analysis revealed accumulation of inflammatory cells and severe interstitial and perivascular fibrosis in COX2~(-/-)cardiac tissues.Moreover,cardiac ATP and acetyl-Co A production was dramatically decreased in COX2~(-/-)rats.Consistently,the expression of genes related to mitochondrial oxidation,such as those that encode for subunits of pyruvate dehydrogenase complex and acyl Co A dehydrogenases,were downregulated,while glycolytic hexokinase 1 (HK1) was upregulated in COX2~(-/-)heart tissues.These observations indicate that COX2-deficient rats developed spontaneously heart failure,likely as a result of dysregulated cardiac energy metabolism. 相似文献
993.
Yang Teng Shi Yu Zhu Jun Zhao Chang Wang Jianmei Liu Zhiyong Fu Xiao Liu Xu Yan Jiangwei Yuan Meiqing Chu Haiyan 《中国科学:生命科学英文版》2021,64(9):1546-1559
Urban soils harbor billions of bacterial cells and millions of species. However, the distribution patterns and assembly processes of bacterial communities remain largely uncharacterized in urban soils. It is also unknown if we can use the bacteria to track soil sources to certain cities and districts. Here, Illumina MiSeq sequencing was used to survey soil bacterial communities from 529 random plots spanning 61 districts and 10 major cities in China. Over a 3,000 km range, community similarity declined with increasing geographic distance(Mantel r=0.62), and community composition was clustered by city(R~2=0.50). Within cities(100 km), the aforementioned biogeographic patterns were weakened. Process analysis showed that homogenizing dispersal and dispersal limitation dominated soil bacterial assembly at small and large spatial scales, respectively. Accordingly, the probabilities of accurately tracking random soil sources to certain cities and districts were 90.0% and 66.7%, respectively. When the tested samples originated from cities that were more than 1,265 km apart, the soil sources could be identified with nearly 100% accuracy. Overall, this study demonstrates the strong distance-decay relationship and the clear geographic zoning of urban soil bacterial communities among cities. The varied importance of different community assembly processes at multiple spatial scales strongly affects the accuracy of microbial source tracking. 相似文献
994.
Ran Chao Li Yu Ma Xufa Xie Yadong Xie Mingxu Zhang Yuting Zhou Wei Yang Yalin Zhang Zhen Zhou Li Wei Kaijian Zhou Zhigang 《中国科学:生命科学英文版》2021,64(9):1437-1448
Viral diseases cause serious economic loss in farmed animals industry. However, the efficacy of remedies for viral infection in farmed animals is limited, and treatment strategies are generally lacking for aquatic animals. Interactions of commensal microbiota and viral infection have been studied in recent years, demonstrating a third player in the interaction between hosts and viruses. Here, we discuss recent developments in the research of interactions between commensal bacteria and viral infection,including both promotion and inhibition effect of commensal bacteria on viral pathogenesis, as well as the impact of viral infection on commensal microbiota. The antiviral effect of commensal bacteria is mostly achieved through priming or regulation of the host immune responses, involving differential microbial components and host signaling pathways, and gives rise to various antiviral probiotics. Moreover, we summarize studies related to the interaction between commensal bacteria and viral infection in farmed animals, including pigs, chickens, fish and invertebrate species. Further studies in this area will deepen our understanding of antiviral immunity of farmed animals in the context of commensal microbiota, and promote the development of novel strategies for treatment of viral diseases in farmed animals. 相似文献
995.
目的:为提高CRISPR/Cas9(clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9)靶向性奠定基础,同时证明酵母杂交系统在研究CRISPR/Cas9脱靶效应中的应用价值。方法:以实验室前期构建成功的activase基因编辑水稻株为研究对象,先采用T7核酸内切酶Ⅰ法初步预测30株基因编辑水稻株的脱靶率。随后以酵母杂交系统进一步预测脱靶率以及研究sgRNA结构对脱靶率的影响。首先,将activase靶向基因的标准sgRNA(standard sgRNA)和短sgRNA(truncated sgRNA)分别克隆至CRISPR/Cas9系统表达载体pDW3769中,构建对应的重组载体pHZ2和pHZ4,转化至YPH499酵母单倍体形成重组酵母YpHZ2和YpHZ4;其次,根据脱靶位点预测选择7组脱靶序列A、B、C、D、E、F、G以及靶向序列,分别克隆至包含报告基因mCherry的高拷贝载体pDW3133和低拷贝载体pDW3134,构建相应的高拷贝重组载体pHZ5、pHZ7、pHZ9、pHZ11、pHZ13、pHZ15、pHZ17和pHZ19,以及对应的低拷贝重组载体pHZ6、pHZ8、pHZ10、pHZ12、pHZ14、pHZ16、pHZ18和pHZ20,转化至YPH500酵母单倍体,构建重组酵母YpHZ5-20。随后,重组酵母YpHZ2和YpHZ4与重组酵母YpHZ5-20分别杂交,挑取双倍体酵母菌落,在不同的时间段下检测荧光数值,根据荧光值定量预测脱靶率。结果:酵母培养144~192 h时荧光最为显著,脱靶序列sgRNA与靶向基因sgRNA同源性越高,越易造成脱靶,但短sgRNA较标准sgRNA脱靶率低。根据水稻植株的脱靶检测显示脱靶率约20%,基于酵母杂交的检测结果显示脱靶率为20%~28%。结论:酵母细胞进入稳定期时荧光值最为显著,且与载体的拷贝数量成正比。sgRNA序列以及长短结构可影响CRISPR/Cas9的基因靶向性。两种方法的脱靶率预测结果相当,表明酵母杂交系统在评价CRISPR/Cas9系统的脱靶率以及研究脱靶影响因素中具有良好的应用价值。 相似文献
996.
Drought stress has detrimental effects on plants. Although the abscisic acid (ABA)‐mediated drought response is well established, defensive mechanisms to cope with dehydration‐induced proteotoxicity have been rarely studied. DRR1 was identified as an Arabidopsis drought‐induced gene encoding an ER‐localized RING‐type E3 Ub ligase. Suppression of DRR1 markedly reduced tolerance to drought and proteotoxic stress without altering ABA‐mediated germination and stomatal movement. Proteotoxicity‐ and dehydration‐induced insoluble ubiquitinated protein accumulation was more obvious in DRR1 loss‐of‐function plants than in wild‐type plants. These results suggest that DRR1 is involved in an ABA‐independent drought stress response possibly through the mitigation of dehydration‐induced proteotoxic stress. 相似文献
997.
Jie Wang Long‐Jiang Yu Wenda Wang Qiujing Yan Tingyun Kuang Xiaochun Qin Jian‐Ren Shen 《植物学报(英文版)》2021,63(7):1367-1381
Photosystem I (PSI) is one of the two photosystems in photosynthesis, and performs a series of electron transfer reactions leading to the reduction of ferredoxin. In higher plants, PSI is surrounded by four light-harvesting complex I (LHCI) subunits, which harvest and transfer energy efficiently to the PSI core. The crystal structure of PSI-LHCI supercomplex has been analyzed up to 2.6 Å resolution, providing much information on the arrangement of proteins and cofactors in this complicated supercomplex. Here we have optimized crystallization conditions, and analyzed the crystal structure of PSI-LHCI at 2.4 Å resolution. Our structure showed some shift of the LHCI, especially the Lhca4 subunit, away from the PSI core, suggesting the indirect connection and inefficiency of energy transfer from this Lhca subunit to the PSI core. We identified five new lipids in the structure, most of them are located in the gap region between the Lhca subunits and the PSI core. These lipid molecules may play important roles in binding of the Lhca subunits to the core, as well as in the assembly of the supercomplex. The present results thus provide novel information for the elucidation of the mechanisms for the light-energy harvesting, transfer and assembly of this supercomplex. 相似文献
998.
Li Zhengtu Li Yinhu Sun Ruilin Li Shaoqiang Chen Lingdan Zhan Yangqing Xie Mingzhou Yang Jiasheng Wang Yanqun Zhu Airu Gu Guoping Yu Le Li Shuaicheng Liu Tingting Chen Zhaoming Jian Wenhua Jiang Qian Su Xiaofen Gu Weili Chen Liyan Cheng Jing Zhao Jincun Lu Wenju Zheng Jinping Li Shiyue Zhong Nanshan Ye Feng 《中国科学:生命科学英文版》2021,64(12):2129-2143
Science China Life Sciences - Prolonged viral RNA shedding and recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in coronavirus disease 2019 (COVID-19) patients have been... 相似文献
999.
Science China Life Sciences - The original article has been corrected. 相似文献
1000.
Jun Liu Junchen Chen Yadan Zhong Xiaoling Yu Ping Lu Jianqi Feng Xin Zhang Shufeng Ma Chao Yang Bin Yang Zhili Rong 《蛋白质与细胞》2021,12(8):653-660
Dear Editor,
Primary localized cutaneous amyloidosis (PLCA) is a skin-limited disorder characterized by deposition of amyloid material in the superficial dermis.According to clinical characteristics,PLCA is divided into lichen,macular,and nodular amyloidosis.PLCA is found worldwide but has a higher incidence in South America and Southeast Asia,such as in Brazil and China (Chang et al.,2014;Tey et al.,2016). 相似文献