Presence of branched portion in poly(adenosine diphosphate ribose) in vivo.

Abstract

The existence of the branched portion of poly(ADPribose) in vivo was demonstrated by a very sensitive and selective new method.Rat liver was freezeclamped and mixed with p~ly(['~C]ADP-ribose) synthesized in vitro as a tracer.Authentic p~ly(['~C]ADP-ribose) was hydrolyzed by snake venom phosphodiesterase to three compounds: 2'-ribo~yl-[~~C]adenosine-5',5''bis(phosphate), the major hydrolysis product; ["C] AMP, derived from the terminus; and 2' [l"-ribosyl-2"(1"'-rib~syl)]['~Cjadenosine -5',5'',5'"tris(phosprobably derived from the branched portion of poly(ADP-ribose) (Miwa, M., Ishihara, M., Takishima,