Cytoplasmic poly(ADP-ribose) polymerase associated with free messenger ribonucleoprotein particles in rat brain.
Poly(ADP-ribose) polymerase associated with free cytoplasmic messenger ribonucleoprotein particles (free mRNP particles) carrying messenger RNA has been characterized in rat brain. There were first-order kinetics for NAD with an apparent Km for NAD of 90.5 +/- 0.70 microM and Vmax of 19.7 +/- 2.8 pmol ADP-ribose incorporated min-1 mg protein-1. Five poly(ADP-ribose) protein acceptors were identified in the Mr 37,000-120,000 range. It is hypothesized that ADP-ribosylation of specific free mRNP proteins might play a role in the derepression and translation of the silent mRNAs of free mRNP particles.
D000818:Animals; D001921:Brain / Q000201:enzymology* / Q000648:ultrastructure; D002413:Cations, Divalent / Q000494:pharmacology; D007700:Kinetics; D009243:NAD / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D051381:Rats; D012261:Ribonucleoproteins / Q000378:metabolism*
D002413:Cations, Divalent; D012261:Ribonucleoproteins; C026452:messenger ribonucleoprotein; D009243:NAD; D011065:Poly(ADP-ribose) Polymerases