Nuclear incorporation of [adenine 14C]NAD is altered by compounds which affect poly(ADP-ribose) formation.

The use of a DNA alkylating agent, which induces poly(ADP-ribose) formation, has been employed to study the incorporation of [adenine 14C]NAD into pea root meristem nuclei, which is a prerequisite for poly(ADP-ribose) synthesis. The incorporation of [adenine 14C]NAD is significantly reduced when the poly(ADP-ribose)polymerase inhibitors, 7-methylxanthine and 3-methoxybenzamide are present and this incorporation is augmented when the DNA alkylating agent methyl methanesulfonate is added. Such information supports the hypothesis that poly(ADP-ribose) may be involved in the cell cycle regulation of pea root meristem nuclei.