Poly(ADP-ribose) polymerase-1 cleavage during apoptosis: an update.
Poly(ADP-ribosylation) is a post-translational modification of proteins playing a crucial role in many processes, including DNA repair and cell death. The best known poly(ADP-ribosylating) enzyme, PARP-1, is a DNA nick sensor and uses betaNAD(+) to form polymers of ADP-ribose which are further bound to nuclear protein acceptors. To strictly regulate poly(ADP-ribose) turnover, its degradation is assured by the enzyme poly(ADP-ribose) glycohydrolase (PARG). During apoptosis, PARP-1 plays two opposite roles: its stimulation leads to poly(ADP-ribose) synthesis, whereas caspases cause PARP-1 cleavage and inactivation. PARP-1 proteolysis produces an 89 kDa C-terminal fragment, with a reduced catalytic activity, and a 24 kDa N-terminal peptide, which retains the DNA binding domains. The fate and the possible role of these fragments during apoptosis will be discussed.
Soldani
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Dipartimento di Biologia Animale, University of Pavia, Piazza Botta 10, Italy.
Scovassi
A Ivana
AI
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001327:Autoimmune Diseases / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D004260:DNA Repair / Q000502:physiology; D051379:Mice; D009336:Necrosis; D010447:Peptide Hydrolases / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*
D011065:Poly(ADP-ribose) Polymerases; D010447:Peptide Hydrolases