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Hydrobiologia - UV-B radiation is an increasing threat to aquatic organisms and also a potential driving force for zooplankton population dynamics. To explore the ecological effects of UVR on... 相似文献
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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
996.
Zhou Yang Cao Leqing Guo Huidong Hong Yan Wang Ming Wang Ke Huang Xiaojun Chang Yingjun 《中国科学:生命科学英文版》2021,64(7):1087-1096
Acute graft-versus-host disease(a GVHD) is caused by allo-activated donor T cells infiltrating target organs. As a regulator of immune function, granulocyte colony-stimulating factor(G-CSF) has been demonstrated to relieve the a GVHD reaction.However, the role of G-CSF-primed donor Tcells in specific target organs is still unknown. In this study, we employed a classical MHC-mismatched transplantation mouse model(C57BL/6 into BALB/c) and found that recipient mice transplanted with GCSF-primed T cells exhibited prolonged survival compared with that of the PBS-treated group. This protective function against GVHD mediated by G-CSF-primed donor T cells was further confirmed by decreased clinical and pathological scores in this a GVHD mouse model, especially in the lung and gut. Moreover, we found that Tcells polarized towards Th2 cells and regulatory T cells were increased in specific target organs. In addition, G-CSF treatment inhibited inducible co-stimulator(ICOS) expression and increased the expression of tolerance-related genes in recipient mice. Our study provides new insight into the immune regulatory effects of G-CSF on T cell-mediated a GVHD, especially for its precise regulation in GVHD target organs. 相似文献
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Chen Jiakui Li Gaofei Lian Junwei Ma Ning Huang Zhibin Li Jianchao Wen Zilong Zhang Wenqing Zhang Yiyue 《中国科学:生命科学英文版》2021,64(12):2186-2201
Science China Life Sciences - Hematopoietic stem and progenitor cells (HSPCs) are able to self-renew and can give rise to all blood lineages throughout their lifetime, yet the mechanisms regulating... 相似文献
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Plant extracellular vesicles (EVs) play critical roles in the cross-kingdom trafficking of molecules from hosts to interacting microbes, most notably in plant defense responses. However, the isolation of pure, intact EVs from plants remains challenging. A variety of methods have been utilized to isolate plant EVs from apoplastic washing fluid (AWF). Here, we compare published plant EV isolation methods, and provide our recommended method for the isolation and purification of plant EVs. This method includes a detailed protocol for clean AWF collection from Arabidopsis thaliana leaves, followed by EV isolation via differential centrifugation. To further separate and purify specific subclasses of EVs from heterogeneous vesicle populations, density gradient ultracentrifugation and immunoaffinity capture are then utilized. We found that immunoaffinity capture is the most precise method for specific EV subclass isolation when suitable specific EV biomarkers and their corresponding antibodies are available. Overall, this study provides a guide for the selection and optimization of EV isolation methods for desired downstream applications. 相似文献
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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
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