Sequences in rotavirus glycoprotein VP7 that mediate delayed translocation and retention of the protein in the endoplasmic reticulum.

摘要: Glycosylation and translocation of the simian rotavirus protein VP7, a resident ER protein, does not occur co-translationally in vivo. In pulse-chase experiments COS cells, nonglycosylated VP7 was still detectable after 25-min chase period, although single glycosylation site only 18 residues beyond signal peptide cleavage site. After labeling, glycosylated recovered microsomes but latter sensitive to trypsin (i.e., nascent became membrane associated) most it entered posttranslationally because rate-limiting step early translocation. contrast with bovine translocated rapidly. Thus, delayed per se required for retention ER. By constructing hybrid proteins, further shown that together 64-111 caused The same sequences were also necessary sufficient data are consistent idea certain proteins inserted into loop configuration.