VIRAL MEMBRANE AND GLYCOPROTEIN STRUCTURE

描述：(逐字摘自申请人的摘要)新发感染：至 研究流感病毒株产生传染性的机制 对于人类，我们计划检查X光的结构和功能 病毒株的血凝素显然仅限于感染动物 用于比较来自主要疫区的人类感染株 大流行。细胞受体上不同唾液酸苷连接的偏好 与感染在动物与人类之间的传播有关。其中一个目标是 帮助解释观察到的现象，如为什么过去两年香港爆发疫情 禽流感病毒在人类中的感染没有蔓延到人类人口中。 病毒进入机制：为了研究流感病毒的膜融合，我们 完整HA和洗涤剂蛋白质/洗涤剂复合体的平面晶体结构研究 HA与膜相互作用的HA2及其机理研究 聚变反应中的中间体。低pH条件下HA2的假说 结晶学观察到的构象是膜熔融活性也会 用完整的重组HA2分子在适合于 膜融合试验。假设N-末端和C-末端片段 HA1加上全部HA2(BHA的茎)是祖先膜融合蛋白Will 通过对这样的蛋白质进行工程测试，测试它是否可以 蛋白水解性启动和低pH激活，以及HA1片段是否 具有一定的作用，例如在含有以下物质的假定多三聚体的组装中 毛孔。 M2离子通道：生成有关离子通道的结构信息 流感病毒M2蛋白我们建议在洗涤剂中结晶 我们生产的细菌化表达和复性的M2四聚体；和/或 具有通道活性的合成跨膜螺旋的四聚体。复合体与 抑制性药物金刚烷胺也将被研究。

Description: (Verbatim from the applicant's abstract) Emerging Infections: To study the mechanism by which influenza virus strains can emerge as infectious to humans, we plan to examine the X-ray structure and function of hemagglutinins from viral strains apparently limited to infecting animal reservoirs and for comparison human infectious strains from the major pandemics. Preferences for different sialoside linkages on cellular receptors correlate with the spread of infection in animals versus humans. One goal is to help explain observations like why outbreaks in the past two years in Hong Kong of avian virus infections in humans did not spread into the human population. Viral Entry Mechanisms: To investigate membrane fusion by influenza virus, we plan crystal structure studies of protein/detergent complexes of intact HA and HA2 and mechanistic studies of the interaction of HA with membranes and of intermediates in the fusion reaction. The hypothesis that HA2 in the low pH conformation observed by crystallography is membrane fusion active will also be tested with intact recombinant HA2 molecules transfected in cells suitable for membrane fusion assays. The hypothesis that the N- and C-terminal segments of HA1 plus all of HA2 (BHA's stem) was an ancestral membrane fusion protein will be tested by engineering such a protein, testing whether it can be proteolytically primed and activated by low pH, and whether the HA1 segments have a role, such as in the assembly of a putative multi-trimer containing pore. M2 Ion Channel: To generate structural information about the ion channel protein M2 of influenza virus we propose crystallization in detergent of bacterially expressed and refolded M2 tetramers that we have produced; and/or a tetramer of a channel-active synthetic transmembrane helix. Complexes with the inhibitory drug, amantadine, will also be studied.