Characterization of proteins encoded by the short unique region of herpesvirus of turkeys by in vitro expression.

Nine open reading frames mapping in the short unique (US) region of the genome of herpesvirus of turkeys (HVT) were expressed by in vitro transcription and translation. The observed M(r)s of US10, SORF3 and US2 were as predicted from the sequence but there were discrepancies between the observed and predicted M(r)s of US1, protein kinase, gI, gD and gE. These could be accounted for in most cases by post-translational and co-translational processing. Analysis of the synthesized products at different time points provided evidence for post-translational modification of HVT protein kinase. Translation in the presence of microsomal membranes resulted in co-translational processing of HVT gD, gI and gE by glycosylation and signal peptide cleavage.