PRIMARY CLEAVAGE OF THE HAV CAPSID PROTEIN-PRECURSOR IN THE MIDDLE OF THE PROPOSED 2A CODING REGION

Portions of the P1 and P2 hepatitis A virus (HAV) polyprotein were generated by in vitro translation of cDNA transcripts and analyzed for a primary cleavage reaction that would release the capsid protein precursor. No autocatalytic activity was observed on either side of the 2A coding sequence. Incubation of these proteins with an extract containing active HAV 3C protease, however, resulted in cleavage at a position approximately 40 amino acids downstream of the previously proposed P1-2A junction. This cleavage site likely accounts for the VP1-containing proteins of approximately 38-40 kDa observed in HAV-infected cells. © 1993 Academic Press, Inc.