The Rev Axis of HIV-1 and Its Associated Host Cofactors: A Viral Window onto the Workings of Eukaryotic Posttranscriptional RNA Processing.
The Rev axis of HIV is one of two key autoregulatory pathways required for viral replication and pathogenesis. The viral Rev protein interacts with its RNA target sequence, the RRE, to overcome the inhibitory effects of constitutive repressor sequences and promote nucleocytoplasmic transport and expression of viral RNAs. The Rev axis is the subject of intense scrutiny not only because it plays a central role in the viral life cycle, but also because it offers a window onto the workings of key mechanisms of posttranscriptional regulation, including splicing, polyadenylation, degradation, transport, and translation. Recent reports have conclusively demonstrated a central role for transport in the Rev mechanism and have identified cellular factors that are good candidates for mediating the transport phenomena. Other potentially involved cellular factors are being investigated. Much of the apparent heterogeneity in the observed effects of Rev may actually derive from heterogeneity in the constitutive repressor sequences rather than from heterogeneity in the mechanism of action of Rev per se. Copyright 1996 S. Karger AG, Basel
Dayton
A.I.
AI
Laboratory of Molecular Virology, Division of Transfusion-Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Bethesda, Md., USA.