POLIOVIRUS RECEPTOR AND INTERACTIONS WITH POLIOVIRUS

人受体与受体之间相互作用的分子参数 脊髓灰质炎病毒（hPVR），一种80 kD Ig样细胞表面糖蛋白， 一般结构域V-C_2-C_2，并对脊髓灰质炎病毒进行了研究。 这将涉及hPVR多肽的特异性改变， 诱变和病毒突变体的遗传分析。 受体变体 将在小鼠细胞中表达用于功能研究。 此外，本发明还提供了一种方法， 受体变体将在CHO细胞中过表达， 适于结晶和X射线的纯化蛋白质的量 分析和受体/病毒的冷冻电子显微镜研究 复杂. 这些结构研究将与M.G. 罗斯曼 脊髓灰质炎病毒感染动物研究中的一个谜是 受体mRNA和多肽明显广泛表达 与一组有限的靶组织相比。 为了识别基因 负责表达的元件，hPVR基因的启动子将 在组织培养细胞中进行解剖和研究， 分离顺式作用序列和反式作用因子。 此外，委员会认为， hPVR启动子调控的表达将通过生殖系研究 小鼠的转化和与不同片段连接的lacZ基因 hPVR基因启动子。 确定hPVR可能的相互作用 通过细胞质结构域与细胞内蛋白质结合， 将采用在酵母中使用双杂交系统。 这些研究 将包括hPVR和淋巴细胞归巢之间可能的相互作用 受体CD 44。 最后，小鼠神经毒力的遗传决定因素 PV 1（LS-a）是一种脊髓灰质炎病毒株， 衣壳蛋白的编码序列之外的基因组序列。

Molecular parameters of the interaction between the human receptor for poliovirus (hPVR), a 80 kD Ig-like, cell-surface glycoprotein with a general domain structure V-C2-C2, and the poliovirion will e studied. This will involve specific changes of hPVR polypeptide by site-directed mutagenesis, and genetic analyses of viral mutants. Receptor variants will be expressed in mouse cells for functional studies. In addition, receptor variants will be over-expressed in CHO cells to produce large quantities of purified protein suitable for crystallization and X-ray analysis, and for cryoelectron microscopic studies of the receptor/virus complex. These structural studies will be a collaboration with M.G. Rossmann. An enigma in research of poliovirus infection of animals is the apparent widespread expression of receptor mRNA and polypeptides contrasted with a limited set of target tissues. To identify genetic elements responsible for expression, the promoter of the hPVR gene will be dissected and studied in tissue culture cell with the objective to isolate cis-acting sequences and trans-acting factors. Moreover, expression regulated by the hPVR promoter will be studied by germline transformation of mice and the gene for lacZ linked to different segments of the hPVR gene promoter. To determine possible interactions of hPVR with intracellular proteins via the cytoplasmic domains, a genetic screen employing the two-hybrid system in yeast will be employed. These studies will include possible interactions between hPVR and the lymphocyte homing receptor CD44. Finally, the genetic determinants of mouse neurovirulence of PV1(LS-a), a strain of poliovirus, will be studied with attention to genomic sequences outside the coding sequence for the capsid protein.