The genes pme-1 and pme-2 encode two poly(ADP-ribose) polymerases in Caenorhabditis elegans.
Poly(ADP-ribose) polymerases (PARPs) are an expanding, well-conserved family of enzymes found in many metazoan species, including plants. The enzyme catalyses poly(ADP-ribosyl)ation, a post-translational modification that is important in DNA repair and programmed cell death. In the present study, we report the finding of an endogenous source of poly(ADP-ribosyl)ation in total extracts of the nematode Caenorhabditis elegans. Two cDNAs encoding highly similar proteins to human PARP-1 (huPARP-1) and huPARP-2 are described, and we propose to name the corresponding enzymes poly(ADP-ribose) metabolism enzyme 1 (PME-1) and PME-2 respectively. PME-1 (108 kDa) shares 31% identity with huPARP-1 and has an overall structure similar to other PARP-1 subfamily members. It contains sequences having considerable similarity to zinc-finger motifs I and II, as well as with the catalytic domain of huPARP-1. PME-2 (61 kDa) has structural similarities with the catalytic domain of PARPs in general and shares 24% identity with huPARP-2. Recombinant PME-1 and PME-2 display PARP activity, which may partially account for the similar activity found in the worm. A partial duplication of the pme-1 gene with pseudogene-like features was found in the nematode genome. Messenger RNA for pme-1 are 5'-tagged with splice leader 1, whereas those for pme - 2 are tagged with splice leader 2, suggesting an operon-like expression for pme - 2. The expression pattern of pme-1 and pme-2 is also developmentally regulated. Together, these results show that PARP-1 and -2 are conserved in evolution and must have important functions in multicellular organisms. We propose using C. elegans as a model to understand better the functions of these enzymes.
Gagnon
Steve N
SN
Department of Pediatrics, Laval University Medical Research Centre and Faculty of Medicine, Laval University, Quebec, Canada.
Hengartner
Michael O
MO
Desnoyers
Serge
S
D000818:Animals; D017173:Caenorhabditis elegans / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D005786:Gene Expression Regulation; D017238:Genes, Helminth / Q000235:genetics*; D008969:Molecular Sequence Data; D011064:Poly Adenosine Diphosphate Ribose / Q000096:biosynthesis; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D011994:Recombinant Proteins / Q000378:metabolism
D018076:DNA, Complementary; D012333:RNA, Messenger; D011994:Recombinant Proteins; D011064:Poly Adenosine Diphosphate Ribose; D011065:Poly(ADP-ribose) Polymerases