人星状病毒非结构蛋白nsP1a C末端结构域致宿主细胞凋亡的机制

项目名称： 人星状病毒非结构蛋白nsP1a C末端结构域致宿主细胞凋亡的机制

项目编号： No.81201285

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 医学四处

项目作者： 赵微

作者单位： 辽宁医学院

项目金额： 23万元

中文摘要： 人星状病毒（Human astrovirus，HAstV）是导致婴幼儿腹泻的重要病原体，但HAstV致腹泻的原因尚不明确。目前认为，肠上皮细胞凋亡是诱发腹泻的主要原因之一。课题组前期研究显示，HAstV I 能够诱导人结肠癌细胞Caco2凋亡，而病毒非结构蛋白nsP1a在诱导凋亡中起关键作用。进一步研究证实，凋亡作用是通过nsP1a 蛋白C末端（nsP1a/4）实现的，删除nsP1a/4后nsP1a不能再诱导凋亡。但nsP1a/4诱导凋亡的具体分子机制尚不清楚。本项目在前期工作的基础上，从nsP1a/4蛋白和细胞相互作用的角度出发，深入探讨nsP1a/4诱导凋亡的分子机制，进而鉴定促凋亡作用的关键氨基酸。采用GST-pulldwon和免疫共沉淀技术对Caco2细胞蛋白与nsP1a/4蛋白的相互作用进行初步探讨，从而为阐明HAstV致病机理奠定基础，同时也为防治HAstV腹泻提供新的线索。

中文关键词： 星状病毒；凋亡；非结构蛋白；蛋白互作；分子机制

英文摘要： Human astroviruses（HAstV） are important pathogens that cause acute viral diarrhea in infants. Little is known about the mechanisms of astrovirus-induced diarrhea. Several lines of evidence has demonstrated that intestinal epithelial cells apoptosis plays a critical role in the events leading to diarrhea. Unfortunately, whether human astrovirus could induce apoptosis in intestinal epithelial cells was not examined. Caco2 cell derived from human colon carcinoma cell, which morphologically and functionally resembles the enterocytes lining the small intestine, is widely used as an in vitro model of the human small intestinal mucosa. We found that HAstV-I can induce Caco2 apoptosis. To further explore the mechanism of HAstV-I induced apoptosis of Caco2, we transfected HAstV-I non-structural protein nsP1a, nsP1b and coat protein ORF2 recombinants with GFP tag into Caco2 cells, respectively. The results revealed that nsP1a can induce apoptosis, however nsP1b and ORF2 can't induce apoptosis, suggesting nsP1a is involved in HAstV-I induced apoptosis. We further transfected the mutant in which nsP1a/4 was deleted into Caco2 cells, we found this mutant can't induce apoptosis of Caco2.Based on these data, we proposed that nsP1a/4 protein plays a critical role in HAstV-induced apoptosis. But the cellular and molecule mechani

英文关键词： astrovirus；apoptosis；non structural protein；protein protein interaction；biology mechanism