Regulation of the replication of influenza virus RNA segments: partial suppression of protein synthesis restores the 'early' replication pattern.
The replication of influenza virus RNA was monitored by RNA-RNA hybridization with subsequent analysis of hybrid duplexes, as well as by immunosorption of viral nucleocapsids from extracts of [3H]uridine-labelled cells followed by the isolation and characterization of nucleocapsid-associated RNA. The nucleocapsid-associated RNA preparations contained mostly negative-strand genomic RNA. Electrophoresis of the hybrid RNA duplexes or single-stranded nucleocapsid-associated RNA in polyacrylamide gel revealed an 'early' replication pattern, with a predominance of the NP and NS gene segments, in cells labelled from 0 to 1 h post-infection. At later stages of infection the pattern changed to the 'late' one, with the M gene segment in excess of NS, and the NP gene no longer predominant. Cycloheximide added as late as 2 or 3 h post-infection suppressed RNA replication. Moderate concentrations of cycloheximide inhibited the replication of NS and NP gene segments to a lesser degree than the replication of the other RNA segments, thus restoring the 'early' replication pattern. Cycloheximide treatment resulted in a slight increase in the percentage of positive strands in nucleocapsid-associated RNA. The role of protein synthesis in the transition from the 'early' to the 'late' pattern of influenza virus RNA synthesis is discussed.
D000818:Animals; D002213:Capsid / Q000378:metabolism; D002642:Chick Embryo; D003513:Cycloheximide / Q000494:pharmacology; D009980:Influenza A virus / Q000235:genetics* / Q000254:growth & development; D011061:Poly A / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger; D012367:RNA, Viral / Q000096:biosynthesis*; D012261:Ribonucleoproteins / Q000378:metabolism; D013997:Time Factors; D014758:Viral Core Proteins / Q000378:metabolism; D014779:Virus Replication
D012333:RNA, Messenger; D012367:RNA, Viral; D012261:Ribonucleoproteins; D014758:Viral Core Proteins; D011061:Poly A; D012313:RNA; D003513:Cycloheximide