Fate of Histone Messenger RNA in Mengovirus‐Infected Ehrlich Ascites Tumor Cells

Abstract

Histone mRNA was isolated from mengovirus‐infected Ehrlich ascites tumor cells at various times postinfection and quantitated in a reticulocyte cell‐free protein‐synthesizing system. The amount of translatable histone mRNA decreases during the first hour postinfection by 30%, rises during the following 1–1.5 h by 10–15%, drops progressively in the further course of infection, and reaches 20% of the control at the end of the infectious cycle (8–9 h postinfection). On the basis of the relative histone mRNA contents, the histone‐synthesizing potentials of mengovirus‐infected Ehrlich ascites tumor cells are substantially higher throughout infection than actually expressed in vivo. This result indicates that the virus‐induced shutoff of histone synthesis is not directly the consequence of inactivation or degradation of histone mRNA. Most of the histone mRNA recovered from mengovirus‐infected Ehrlich ascites tumor cells is bound to ribosomes. Late in infection, certain mRNAs are co‐isolated with histone mRNAs, very likely due to loss or shortening of poly(A) occurring after release of the mRNAs from polyribosomes. Copyright © 1977, Wiley Blackwell. All rights reserved