[Phosphorylation and other properties of proteins binding single-stranded DNA (SSB-proteins) from chromatin and extrachromatin fractions of Ehrlich ascites carcinoma].
A comparative study of single-stranded DNA-binding proteins (SSB-proteins) isolated from chromatin and the extrachromatin fraction of Ehrlich ascites tumour cells was carried out. No differences were found either in SDS-gel electrophoretic mobility or in the single-stranded DNA-binding capacity and stimulation of the replicative synthesis of DNA. However, chromatin SSB-proteins contained 1.4-1.5 times more phosphate than extrachromatin proteins. Both preparations could be phosphorylated in vitro by protein kinase C and cAMP-dependent protein kinase, but the chromatin proteins were phosphorylated in a lesser degree. In parallel with phosphorylation the SSB-proteins displayed a higher binding affinity for ssDNA-cellulose. Phosphorylation can thus be regarded as a means of regulation of the SSB-protein function, in particular, their interaction with chromatin DNA.
Koterov
A N
AN
Novoradovskaia
N A
NA
Pushkareva
N B
NB
Vorotnikov
A V
AV
Nikol'skiĭ
A V
AV
Risnik
V V
VV
D000818:Animals; D002286:Carcinoma, Ehrlich Tumor; D002843:Chromatin; D004273:DNA, Neoplasm / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004589:Electrophoresis, Disc; D051379:Mice; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism
D002843:Chromatin; D004273:DNA, Neoplasm; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D011494:Protein Kinases; D011493:Protein Kinase C
Fosforilirovanie i drugie svoĭstva belkov, sviazyvaiushchikhsia s odnonitevoĭ DNK (SSB-belkov) iz khromatina i vnekhromatinovoĭ fraktsii kletok astsitnoĭ kartsinomy Erlikha.