title: Snm1B interacts with PSF2.
abstract: The protein Snm1B plays a key role in interstrand crosslink (ICL) repair. In a yeast two-hybrid screen we identified the protein PSF2 to bind Snm1B. PSF2 is a member of the GINS complex involved in replication initiation and elongation, and is known to play a role in ICL repair. Snm1B was shown to bind PSF2 in human cells through two regions, strongly to a 144 amino acid N-terminal region and weakly to a second smaller 37 amino acid C-terminal region. Ectopic expression of PSF2 increased the amount of Mus81, a protein component of the endonucleolytic complex involved in ICL repair, co-immunoprecipitating with Snm1B. Moreover, deleting the N-terminal, but not C-terminal region of Snm1B reduced the amount of co-immunoprecipitated Mus81. Conversely, the telomere-binding protein TRF2 competed with PSF2 for binding to the C-terminus of Snm1B, and deletion of this region, but not the N-terminal region, reduced Snm1B chromatin association. We speculate that the N-terminal region of Snm1B forms a complex containing PSF2 and Mus81, while the C-terminal region is important for PSF2-mediated chromatin association.
authors.affiliation: Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, United States of America.
authors.forename: Jay R
authors.initials: JR
authors.lastname: Stringer
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Counter
mesh_terms: D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004720:Endonucleases / Q000378:metabolism; D005090:Exodeoxyribonucleases; D006801:Humans; D047468:Immunoprecipitation; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques
chemical_list: D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D002843:Chromatin; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; C071692:TAP2 protein, human; C493741:DCLRE1B protein, human; D004720:Endonucleases; D005090:Exodeoxyribonucleases; C498772:MUS81 protein, human; D045643:DNA Repair Enzymes