PROTHYMOSIN-ALPHA BINDS TO HISTONE H1 IN-VITRO

Previous studies have shown that prothymosin a (ProT alpha) is a nucle ar acidic protein implicated in cell proliferation. To identify protei ns that interact with ProT alpha. we have used ligand-blotting assays. We report here that purified ProT alpha binds specifically to histone H1 in a dose dependent manner. Polyglutamic acid, an analog of the ce ntral acidic domain of ProT alpha, strongly inhibits the above interac tion, suggesting that the binding of ProT alpha to histone H1 is media ted through its acidic domain.