title: PARP-2 depletion results in lower radiation cell survival but cell line-specific differences in poly(ADP-ribose) levels.
abstract: Poly(ADP-ribose) polymerase-2 (PARP-2) activity contributes to a cells' poly(ADP-ribosyl)ating potential and like PARP-1, has been implicated in several DNA repair pathways including base excision repair and DNA single strand break repair. Here the consequences of its stable depletion in HeLa, U20S, and AS3WT2 cells were examined. All three PARP-2 depleted models showed increased sensitivity to the cell killing effects on ionizing radiation as reported in PARP-2 depleted mouse embryonic fibroblasts providing further evidence for a role in DNA strand break repair. The PARP-2 depleted HeLa cells also showed both higher constitutive and DNA damage-induced levels of polymers of ADP-ribose (PAR) associated with unchanged PARP-1 protein levels, but higher PARP activity and a concomitant lower PARG protein levels and activity. These changes were accompanied by a reduced maximal recruitment of PARP-1, XRCC1, PCNA, and PARG to DNA damage sites. This PAR-associated phenotype could be reversed in HeLa cells on re-expression of PARP-2 and was not seen in U20S and AS3WT2 cells. These results highlight the complexity of the relationship between different members of the PARP family on PAR metabolism and suggest that cell model dependent phenotypes associated with the absence of PARP-2 exist within a common background of radiation sensitivity.
authors.affiliation: Institut Curie, Centre de Recherche, Bât. 110-112, Centre Universitaire, 91405, Orsay, France.
authors.forename: Mohammed-Tayyib
authors.initials: MT
authors.lastname: Boudra
authors.forename: Celeste
authors.initials: C
authors.lastname: Bolin
authors.forename: Sara
authors.initials: S
authors.lastname: Chiker
authors.forename: Alexis
authors.initials: A
authors.lastname: Fouquin
authors.forename: Tomasz
authors.initials: T
authors.lastname: Zaremba
authors.forename: Laurence
authors.initials: L
authors.lastname: Vaslin
authors.forename: Denis
authors.initials: D
authors.lastname: Biard
authors.forename: Fabrice P
authors.initials: FP
authors.lastname: Cordelières
authors.forename: Frédérique
authors.initials: F
authors.lastname: Mégnin-Chanet
authors.forename: Vincent
authors.initials: V
authors.lastname: Favaudon
authors.forename: Marie
authors.initials: M
authors.lastname: Fernet
authors.forename: Vincent
authors.initials: V
authors.lastname: Pennaneach
authors.forename: Janet
authors.initials: J
authors.lastname: Hall
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D004249:DNA Damage / Q000528:radiation effects; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism*; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D011839:Radiation, Ionizing; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D004268:DNA-Binding Proteins; D020690:GTPase-Activating Proteins; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D018809:Proliferating Cell Nuclear Antigen; D034741:RNA, Small Interfering; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human; C000619352:Xrcc1 protein, mouse; D011064:Poly Adenosine Diphosphate Ribose; D011065:Poly(ADP-ribose) Polymerases