title: The meiosis-specific recombinase hDmc1 forms ring structures and interacts with hRad51.
abstract: Eukaryotic cells encode two homologs of Escherichia coli RecA protein, Rad51 and Dmc1, which are required for meiotic recombination. Rad51, like E.coli RecA, forms helical nucleoprotein filaments that promote joint molecule and heteroduplex DNA formation. Electron microscopy reveals that the human meiosis-specific recombinase Dmc1 forms ring structures that bind single-stranded (ss) and double-stranded (ds) DNA. The protein binds preferentially to ssDNA tails and gaps in duplex DNA. hDmc1-ssDNA complexes exhibit an irregular, often compacted structure, and promote strand-transfer reactions with homologous duplex DNA. hDmc1 binds duplex DNA with reduced affinity to form nucleoprotein complexes. In contrast to helical RecA/Rad51 filaments, however, Dmc1 filaments are composed of a linear array of stacked protein rings. Consistent with the requirement for two recombinases in meiotic recombination, hDmc1 interacts directly with hRad51.
authors.affiliation: Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Hertfordshire EN6 3LD, UK.
authors.forename: J Y
authors.initials: JY
authors.lastname: Masson
authors.forename: A A
authors.initials: AA
authors.lastname: Davies
authors.forename: N
authors.initials: N
authors.lastname: Hajibagheri
authors.forename: E
authors.initials: E
authors.lastname: Van Dyck
authors.forename: F E
authors.initials: FE
authors.lastname: Benson
authors.forename: A Z
authors.initials: AZ
authors.lastname: Stasiak
authors.forename: A
authors.initials: A
authors.lastname: Stasiak
authors.forename: S C
authors.initials: SC
authors.lastname: West
mesh_terms: D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism* / Q000648:ultrastructure*; D018797:Cell Cycle Proteins; D003001:Cloning, Molecular; D004254:DNA Nucleotidyltransferases / Q000302:isolation & purification / Q000378:metabolism* / Q000648:ultrastructure*; D004277:DNA, Single-Stranded / Q000096:biosynthesis / Q000737:chemistry; D004279:DNA, Viral / Q000096:biosynthesis / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism* / Q000648:ultrastructure*; D004926:Escherichia coli / Q000235:genetics; D015723:Gene Library; D006801:Humans; D019426:Integrases; D008297:Male; D008540:Meiosis; D008854:Microscopy, Electron; D009692:Nucleic Acid Heteroduplexes / Q000096:biosynthesis / Q000737:chemistry; D009928:Organ Specificity; D051135:Rad51 Recombinase; D011938:Rec A Recombinases / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D045522:Recombinases; D011995:Recombination, Genetic; D013737:Testis / Q000201:enzymology
chemical_list: D018797:Cell Cycle Proteins; D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D009692:Nucleic Acid Heteroduplexes; D011994:Recombinant Proteins; D045522:Recombinases; D004254:DNA Nucleotidyltransferases; D019426:Integrases; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; D011938:Rec A Recombinases; C115006:integron integrase IntI1; D000251:Adenosine Triphosphatases; C074556:DMC1 protein, human