Relationship between Poly(Adenosine 5'-diphosphate-ribose) Synthesis and Transcriptional Activity in Wheat Embryo Chromatin.

Chromatin-bound poly(adenosine 5'-diphosphate [ADP]-ribose) synthetase activity was highest in ungerminated wheat (Triticum aestivum L., cv. Mukakomugi) embryos, and it decreased after germination within 14 hours. In contrast, transcriptional activity was lowest in ungerminated wheat embryos, and it increased during germination for 24 hours or more. Histones, H1, H2A/H2B, basic nonhistone chromosomal proteins, and acidic nonhistone chromosomal proteins (molecular weight more than 10 kilodaltons) were ADP-ribosylated in wheat germ chromatin. Specific nonhistone chromosomal protein (molecular weight of 37 kilodaltons) in seedling chromatin was not found to be ADP-ribosylated.