Identification of ribosome-associated viral and cellular basic proteins during the course of infection with herpes simplex virus type 1

Herpes simplex virus type 1 (HSV-1) infection induces severe alterations of the translational apparatus, including the phosphorylation of a few riboso mal proteins, and the progressive association of several nonribosomal prote ins to ribosomes. Therefore, we hypothesized that ribosomes themselves coul d contribute to the HSV-l-induced translational control of host and viral g ene expression. As a prerequisite to test this hypothesis, we undertook the identification of the nonribosomal proteins associated to the ribosomes du ring the course of HSV-1 infection. After separation by two-dimensional pol yacrylamide gel electrophoresis of basic proteins extracted from the riboso mal fraction, the identification of unknown protein spots was carried out b y N-terminal sequencing and peptide mass determination by mass spectrometry . This allowed us to identify HSV-1 VP19C and VP26 that associated to ribos omes with different kinetics. Another nonribosomal protein turned out to be the poly(A)-binding protein 1 (PAB1P). Newly synthesized PAB1P continued t o associate to ribosomes all along infection.