DNA-stimulated protein phosphorylation in HeLa whole cell and nuclear extracts.
Incorporation of 32P from gamma-labeled ATP into a number of polypeptides in HeLa whole cell and nuclear extracts was dependent on added double-stranded DNA or poly(dI-dC), but not denatured or supercoiled DNA. DNA-dependent phosphorylation of a high Mr endogenous substrate could be reconstituted from the precipitate formed after incubation of whole cell extracts with DNA. Fractionation of extracts by phosphocellulose or DEAE-Sephacel chromatography yielded preparations that phosphorylated casein as well as endogenous polypeptides in a DNA-dependent manner. These results are consistent with the existence of a novel protein kinase in HeLa cells that is highly dependent upon the presence of double-stranded DNA for efficient phosphorylation of a variety of substrates.
Carter
T H
TH
Department of Biological Sciences, St. John's University, Jamaica, New York 11439.
Kopman
C R
CR
James
C B
CB
D000255:Adenosine Triphosphate / Q000378:metabolism; D002364:Caseins / Q000378:metabolism; D002474:Cell-Free System; D004247:DNA / Q000494:pharmacology*; D006367:HeLa Cells; D006801:Humans; D066298:In Vitro Techniques; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*
D002364:Caseins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D000255:Adenosine Triphosphate; D004247:DNA; D011494:Protein Kinases