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921.
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923.
924.
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
925.
Jinhua Xiao Xianqin Wei Yi Zhou Zhaozhe Xin Yunheng Miao Hongxia Hou Jiaxing Li Dan Zhao Jing Liu Rui Chen Liming Niu Guangchang Ma Wenquan Zhen Shunmin He Jianxia Wang Xunfan Wei Weihao Dou Zhuoxiao Sui Dawei Huang 《遗传学报》2021,48(3):225-236
Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism. The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes. However, there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators. In fig syconia, there are also non-pollinator species. The non-pollinator species differ in their evolutionary and life histories from pollinators. We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome. The pollinators colonized the figs approximately 66.9 million years ago, consistent with the origin of host figs. Compared with nonpollinators, many more genes in pollinators were subject to relaxed selection. Seven genes were absent in pollinators in response to environmental stress and immune activation. Pollinators had more streamlined gene repertoires in the innate immune system, chemosensory toolbox, and detoxification system. Our results provide genomic evidence for the differentiation between pollinators and nonpollinators. The data suggest that owing to the long-term adaptation to the fig, some genes related to functions no longer required are absent in pollinators. 相似文献
926.
鳞翅目昆虫种类繁多,对农业生产和人类生活产生重大影响,宿主昆虫与病毒相互关系的研究对于利用病毒杀虫剂进行害虫治理和益虫病毒性疾病的预防具有重要意义.因此,鳞翅目昆虫与病毒的互作研究显得尤为重要,宿主昆虫的免疫系统在抗病毒感染过程中发挥着关键作用,对病毒产生不同程度的免疫反应.本文综述了昆虫围食膜和中肠对病毒入侵的防御作用,病毒进入体腔后昆虫所产生的细胞免疫和体液免疫反应,以及RNAi、细胞的自噬与凋亡、Toll、Imd、JAK-STAT和STING信号通路等相关的抗病毒免疫途径,并对昆虫抗病毒免疫研究的制约因素和未来鳞翅目昆虫抗病毒免疫的研究重点进行了讨论,以期为害虫的生物防治和益虫疾病的防控提供理论依据. 相似文献
927.
928.
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
929.
Xingdong Zhou Hui Wang Qun Ji Mingjuan Du Yuexia Liang Huanhuan Li Fan Li Hang Shang Xiujuan Zhu Wei Wang Lichun Jiang Alexey V.Stepanov Tianyu Ma Nanxin Gong Xiaodong Jia Alexander G.Gabibov Zhiyong Lou Yinying Lu Yu Guo Hongkai Zhang Xiaoming Yang 《蛋白质与细胞》2021,12(10):818-823
Dear Editor,
The rapid emergence and persistence of the pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has had enormous impacts on global health and the economy.Effective vaccines against SARS-CoV-2 are urgently needed to control the coronavirus disease 2019(COVID-19) pandemic,and multiple vaccines have been found to be efficacious in preventing symptomatic COVID-19(Polack et al.,2020;Wu et al.,2020;Jones and Roy,2021).We have developed a traditional beta-propiolactone-inacti-vated aluminum hydroxide-adjuvanted whole-virion SARS-CoV-2 vaccine (BBIBP-CorV),which elicited protective immune responses in clinical trials (Wang et al.,2020;Xia et al.,2021).The vaccine has been granted conditional approvals or emergency use authorizations (EUAs) in China and other countries. 相似文献
930.
Zhiguang Zhao Rong Fan Weina Xu Yahui Kou Yangyang Wang Xuehua Ma Zhuo Du 《Molecular systems biology》2021,17(4)
Elucidating the chromatin dynamics that orchestrate embryogenesis is a fundamental question in developmental biology. Here, we exploit position effects on expression as an indicator of chromatin activity and infer the chromatin activity landscape in every lineaged cell during Caenorhabditis elegans early embryogenesis. Systems‐level analyses reveal that chromatin activity distinguishes cellular states and correlates with fate patterning in the early embryos. As cell lineage unfolds, chromatin activity diversifies in a lineage‐dependent manner, with switch‐like changes accompanying anterior–posterior fate asymmetry and characteristic landscapes being established in different cell lineages. Upon tissue differentiation, cellular chromatin from distinct lineages converges according to tissue types but retains stable memories of lineage history, contributing to intra‐tissue cell heterogeneity. However, the chromatin landscapes of cells organized in a left–right symmetric pattern are predetermined to be analogous in early progenitors so as to pre‐set equivalent states. Finally, genome‐wide analysis identifies many regions exhibiting concordant chromatin activity changes that mediate the co‐regulation of functionally related genes during differentiation. Collectively, our study reveals the developmental and genomic dynamics of chromatin activity at the single‐cell level. 相似文献