POLY(ADP-RIBOSE) QUANTIFICATION AT THE FEMTOMOLE LEVEL IN MAMMALIAN-CELLS

ADP-ribose polymers were isolated from living mammalian cells, separat ed by polyacrylamide gel electrophoresis, visualized in the gel with a novel silver staining agent, and quantified by computer-aided scannin g densitometry. This method detects as little as similar to 40 fmol of ADP-ribose polymers of a particular size class and reduces the gel ex posure times required for conventionally radiolabeled polymers from 2 months to about 1 h. The method also detects polymers with slow turnov er which may be underestimated by techniques requiring metabolic radio labeling of poly(ADP-ribose). (C) 1995 Academic Press, Inc.