title: DNA-dependent SUMO modification of PARP-1.
abstract: Poly(ADP-ribose) polymerase 1 (PARP-1) plays an important role in DNA repair, but also contributes to other aspects of nucleic acid metabolism, such as transcriptional regulation. Modification of PARP-1 with the small ubiquitin-related modifier (SUMO) affects its function as a transcriptional co-activator of hypoxia-responsive genes and promotes induction of the heat shock-induced HSP70.1 promoter. We now report that PARP-1 sumoylation is strongly influenced by DNA. Consistent with a function in transcription, we show that sumoylation in vitro is enhanced by binding to intact, but not to damaged DNA, in a manner clearly distinct from the mechanism by which DNA damage stimulates PARP-1's catalytic activity. An enhanced affinity of PARP-1 for the SUMO-conjugating enzyme Ubc9 upon binding to DNA is likely responsible for this effect. Sumoylation does not interfere with the catalytic or DNA-binding properties of PARP-1, and structural analysis reveals no significant impact of SUMO on the conformation of PARP-1's DNA-binding domain. In vivo, sumoylated PARP-1 is associated with chromatin, but the modification is not responsive to DNA damage and is not affected by PARP-1 catalytic activity. Our results suggest that PARP-1's alternative modes of DNA recognition serve as a means to differentiate between distinct aspects of the enzyme's function.
authors.affiliation: Cancer Research UK London Research Institute, Clare Hall Laboratories, Blanche Lane, South Mimms EN6 3LD, United Kingdom.
authors.forename: Nicola
authors.initials: N
authors.lastname: Zilio
authors.forename: Chris T
authors.initials: CT
authors.lastname: Williamson
authors.forename: Sebastian
authors.initials: S
authors.lastname: Eustermann
authors.forename: Rajvee
authors.initials: R
authors.lastname: Shah
authors.forename: Stephen C
authors.initials: SC
authors.lastname: West
authors.forename: David
authors.initials: D
authors.lastname: Neuhaus
authors.forename: Helle D
authors.initials: HD
authors.lastname: Ulrich
mesh_terms: D001483:Base Sequence; D020134:Catalytic Domain; D002843:Chromatin / Q000737:chemistry / Q000502:physiology; D004247:DNA / Q000737:chemistry / Q000502:physiology*; D053960:DNA Breaks; D004268:DNA-Binding Proteins / Q000737:chemistry; D004789:Enzyme Activation; D057809:HEK293 Cells; D006801:Humans; D055029:Inverted Repeat Sequences; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000737:chemistry / Q000502:physiology; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D025842:SUMO-1 Protein / Q000378:metabolism*; D058207:Sumoylation; D044763:Ubiquitin-Conjugating Enzymes / Q000737:chemistry; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D025842:SUMO-1 Protein; D004247:DNA; D044763:Ubiquitin-Conjugating Enzymes; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D000098843:Ubiquitin-Conjugating Enzyme UBC9
keywords: DNA binding; DNA repair; PARP-1; Posttranslational modification; SUMO; Transcription