REGULATION OF THE INTERFERON-INDUCIBLE EIF-2-ALPHA PROTEIN-KINASE BY SMALL RNAS

This review describes the structure and function of the double-strande d RNA-dependent protein kinase (PKR) and its interaction with RNA acti vators and inhibitors. The abilities of small virally-encoded RNAs suc h as VA, RNA of adenovirus, the Epstein-Barr virus encoded (EBER) RNAs and the Tat-responsive region RNA of HIV-1 to bind to and regulate PK R are reviewed, and the physiological implications of such regulation for the control of viral replication and cell growth are discussed. Th e potential effects on the activity of PKR of other proteins that bind double-stranded RNA and/or small viral and cellular RNAs are also con sidered.