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<正>The heavily transmitted and mutated SARS-CoV-2 has constitutes a sustained threat to global health. A recent article published in Nature, firstly provided solid evidence confirming the cross-species transmission of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) from human to free-ranging white-tailed deer(Hale et al., 2022).More importantly, circulation of SARS-CoV-2 among deer rapidly resulted into new phylogenetic clades of deer-only viruses which were believed linkin... 相似文献
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Zhen-Yu Zhang Yin Mai Hao Yang Pei-Yue Dong Xue-Li Zheng Gong-She Yang 《Molecular and cellular biochemistry》2014,395(1-2):53-64
The process of preadipocytes differentiation plays a vital role in adipose tissue expansion and many factors are involved in this event. Cathepsin B (CTSB), secreted from lysosome, has been reported in regulating a variety of physiological processes. In this study, we demonstrated CTSB promotes lipid accumulation and adipogenic genes expression in porcine primary preadipocytes by degrading fibronectin (Fn), a key component of extracellular matrix. Lithium chloride (LiCl) is an activator of Wnt/β-catenin signaling through stabilizing β-catenin. We found that CTSB can relieve the anti-adipogenic effects of LiCl, indicating that CTSB could impact Wnt/β-catenin signaling pathway. Interestingly, Fn is an important target gene of Wnt/β-catenin. So we considered that CTSB promote preadipocytes differentiation by suppressing these two pathways. 相似文献
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以木本植物杨树(Populus sp.)和核桃(Juglans regia L.)为材料,对内源生长素免疫胶体金定位技术在固定、烤片、免疫染色、显色等关键环节进行了改进优化与验证.结果显示,优化后适合木本植物定位方法的主要技术要点是:在染色中,通过采用尿素-胰蛋白酶联合消化技术和增加牛血清白蛋白处理大大地改善了抗原修复结果,提高了染色的敏感性和特异性.利用优化后的方法对核桃幼胚和杨树嫩茎诱导生根过程中的吲哚乙酸(IAA)进行定位研究,发现杨树试管嫩茎生根过程中,形成层及周缘维管束有很强的IAA信号,核桃子叶生根中,胚中有很强的IAA信号,胚根中有半圆形、胚芽中有>"形强信号区,胚轴信号较弱,胚根信号最强.研究表明,与传统免疫染色方法相比,优化后的方法对木本植物生长素定位具有敏感性高,特异性强,银颗粒明显,背景清晰,耗时少等特点. 相似文献
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Zhou L Liu Q Wang Q Ma Y Xu Y Yang Z Zhao Y Zhang Y 《Applied microbiology and biotechnology》2008,79(6):1027-1034
To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development. 相似文献
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Manman Zhang Wenliang Gong Dianjun Zhang Ming Ji Binjie Chen Beina Chen Xinyu Li Yuefei Zhou Chengyi Dong Gehua Wen Xiaoni Zhan Xiafang Wu Lulu Cui Yuliang Feng Siman Wang Huiya Yuan Enyu Xu Maosheng Xia Alexei Verkhratsky Baoman Li 《Cell death & disease》2022,13(4)
Alzheimer’s disease (AD) is the prevalent cause of dementia in the ageing world population. Apolipoprotein E4 (ApoE4) allele is the key genetic risk factor for AD, although the mechanisms linking ApoE4 with neurocognitive impairments and aberrant metabolism remains to be fully characterised. We discovered a significant increase in the ApoE4 content of serum exosomes in old healthy subjects and AD patients carrying ApoE4 allele as compared with healthy adults. Elevated exosomal ApoE4 demonstrated significant inverse correlation with serum level of thyroid hormones and cognitive function. We analysed effects of ApoE4-containing peripheral exosomes on neural cells and neurological outputs in aged or thyroidectomised young mice. Ageing-associated hypothyroidism as well as acute thyroidectomy augmented transport of liver-derived ApoE4 reach exosomes into the brain, where ApoE4 activated nucleotide-binding oligomerisation domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome by increasing cholesterol level in neural cells. This, in turn, affected cognition, locomotion and mood. Our study reveals pathological potential of exosomes-mediated relocation of ApoE4 from the periphery to the brain, this process can represent potential therapeutic target.Subject terms: Cognitive neuroscience, Alzheimer''s disease, Cellular neuroscience 相似文献