Bibb J A, Bernhardt G, Wimmer E
Department of Microbiology, State University of New York at Stony Brook 11794-8621.
J Gen Virol. 1994 Aug;75 ( Pt 8):1875-81. doi: 10.1099/0022-1317-75-8-1875.
We have shown recently that the human poliovirus receptors (hPVRs) expressed on the surface of cultured cells are 80K glycoproteins, whereas the previously reported 67K forms are partially glycosylated intermediate glycoforms. Both the membrane-bound 80K and 67K forms of hPVR are glycosylated derivatives of the two isoforms hPVR alpha and hPVR delta, where the latter two can be resolved only by SDS-PAGE upon enzymatic deglycosylation. Here we report the N-terminal sequence analysis of the mature 80K as well as the intermediate 67K glycoforms of hPVR which has allowed us to identify the signal peptidase cleavage site of the unprocessed hPVR. The signal sequence that directs translocation of hPVR across the membrane of the endoplasmic reticulum on its route to the glycoprocessing pathway has thus been defined. We compare this signal sequence with those of the putative monkey poliovirus receptor and the mouse poliovirus receptor homologue.
我们最近发现，培养细胞表面表达的人脊髓灰质炎病毒受体（hPVR）是80K糖蛋白，而先前报道的67K形式是部分糖基化的中间糖型。膜结合的80K和67K形式的hPVR都是两种亚型hPVRα和hPVRδ的糖基化衍生物，其中后两者只有在酶促去糖基化后通过SDS-PAGE才能分离。在此，我们报告了hPVR成熟80K以及中间67K糖型的N端序列分析，这使我们能够确定未加工hPVR的信号肽切割位点。由此确定了引导hPVR在内质网途径中跨膜转运至糖加工途径的信号序列。我们将该信号序列与推测的猴脊髓灰质炎病毒受体和小鼠脊髓灰质炎病毒受体同源物的信号序列进行了比较。
