Phosphorylation of vaccinia virus core proteins during transcription in vitro.
The phosphorylation of vaccinia virus core proteins has been studied in vitro during viral transcription. The incorporation of [gamma-32P]ATP into protein is linear for the first 2 min of the reaction, whereas incorporation of [3H]UTP into RNA lags for 1 to 2 min before linear synthesis. At least 12 different proteins are phosphorylated on autoradiograms of acrylamide gels, and the majority of label is associated with low-molecular-weight proteins. If the transcription reaction is reduced by dropping the pH to 7 from its optimal of 8.5, two proteins (70 and 80 kDa) are no longer phosphorylated. RNA isolated from the pH 7 transcription reaction hybridized primarily to the vaccinia virus HindIII DNA fragments D to F, whereas the transcripts synthesized at pH 8.5 hybridized to almost all of the HindIII-digested vaccinia virus DNA fragments. The differences between the pH 7.0 and 8.5 transcription reactions in phosphorylation and transcription could be eliminated by preincubating the viral cores with 2 mM ATP. In sum, the results suggest that the phosphorylation of the 70- and 80-kDa peptides may contribute to the regulation of early transcription.
Moussatche
N
N
Instituto de Biofisica Carlos Chagas Filho, Rio de Janeiro, Brazil.
Keller
S J
SJ
D000255:Adenosine Triphosphate / Q000378:metabolism; D004279:DNA, Viral / Q000302:isolation & purification; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010766:Phosphorylation; D012367:RNA, Viral / Q000096:biosynthesis*; D014158:Transcription, Genetic; D014616:Vaccinia virus / Q000378:metabolism*; D014758:Viral Core Proteins / Q000378:metabolism*
D004279:DNA, Viral; D012367:RNA, Viral; D014758:Viral Core Proteins; D000255:Adenosine Triphosphate