title: DNA polymerase mu interacts with a meiosis-specific RecA homolog Lim15 during meiosis in Coprinus cinereus.
abstract: Meiosis is a fundamental process in eukaryotes. Homologous chromosomes are paired and recombined during meiotic prophase I, which results in variation among the gametes. However, the mechanism of recombination between the maternal and paternal chromosome is unknown. In this study, we report on the identification of interaction between Coprinus cinereus DNA polymerase mu (CcPol mu) and CcLim15/Dmc1, a meiosis-specific RecA-like protein, during meiosis. Interaction between these two proteins was confirmed using a GST-pull down assay. A two-hybrid assay revealed that the N-terminus of CcPol mu, which includes the BRCT domain, is responsible for binding the C-terminus of CcLim15. Furthermore, co-immunoprecipitation experiments indicate that these two proteins also interact in the crude extract of the meiotic cell. A significant proportion of CcPol mu and CcLim15 is shown to co-localize in nuclei from the leptotene/zygotene stage to the early pachytene stage during meiotic prophase I. Moreover, CcLim15 enhances polymerase activity of CcPol mu early in the reaction. These results suggest that CcPol mu might be recruited by CcLim15 and elongate the D-loop structure during homologous recombination in meiosis.
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
authors.forename: Takuro
authors.initials: T
authors.lastname: Yanai
authors.forename: Aiko
authors.initials: A
authors.lastname: Sakamoto
authors.forename: Kazuki
authors.initials: K
authors.lastname: Iwabata
authors.forename: Akiyo
authors.initials: A
authors.lastname: Koshiyama
authors.forename: Hiroko
authors.initials: H
authors.lastname: Sugawara
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nara
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Takakusagi
authors.forename: Kengo
authors.initials: K
authors.lastname: Sakaguchi
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism*; D003302:Coprinus / Q000201:enzymology / Q000502:physiology*; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D008540:Meiosis; D025941:Protein Interaction Mapping; D011938:Rec A Recombinases / Q000378:metabolism*; D011995:Recombination, Genetic
chemical_list: D018797:Cell Cycle Proteins; C407743:DNA polymerase mu; D011938:Rec A Recombinases; D004259:DNA-Directed DNA Polymerase