THE USE OF BIOTINYLATED POLY(ADP-RIBOSE) FOR STUDIES ON POLY(ADP-RIBOSE)-PROTEIN INTERACTION

Poly(ADP-ribose) is routinely detected by the use of radioactive polym ers formed from labeled substrates. In this report a simple and time-s aving method for the biotinylation and the detection of poly(ADP-ribos e) on blots is described. The polymer modified by light-induced reacti on with photobiotin was colorimetrically detected and quantified, usin g streptavidine-alkaline phosphatase conjugates. The separation of pol y(ADP-ribose) chains on polyacrylamide gels was not affected by the bi otinylation of the polymers. When biotinylated poly(ADP-ribose) was us ed to detect the poly(ADP-ribose) binding capability of proteins in li gand blots, the results were comparable to those obtained with poly([P -32]ADP-ribose). Experiments with histones and rat liver nuclear prote ins demonstrate that in studies on poly(ADP-ribose)-protein interactio n, this method is applicable to the detection of poly(ADP-ribose) bind ing proteins. (C) 1994 Academic Press, Inc.