title: DNA topoisomerase II interacts with Lim15/Dmc1 in meiosis.
abstract: Lim15/Dmc1 is a meiosis specific RecA-like protein. Here we propose its participation in meiotic chromosome pairing-related events along with DNA topoisomerase II. Analysis of protein-protein interactions using in vitro binding assays provided evidence that Coprinus cinereus DNA topoisomerase II (CcTopII) specifically interacts with C.cinereus Lim15/Dmc1 (CcLim15). Co-immunoprecipitation experiments also indicated that the CcLim15 protein interacts with CcTopII in vivo. Furthermore, a significant proportion of CcLim15 and CcTopII could be shown to co-localize on chromosomes from the leptotene to the zygotene stage. Interestingly, CcLim15 can potently activate the relaxation/catenation activity of CcTopII in vitro, and CcTopII suppresses CcLim15-dependent strand transfer activity. On the other hand, while enhancement of CcLim15's DNA-dependent ATPase activity by CcTopII was found in vitro, the same enzyme activity of CcTopII was inhibited by adding CcLim15. The interaction of CcLim15 and CcTopII may facilitate pairing of homologous chromosomes.
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: Kazuki
authors.initials: K
authors.lastname: Iwabata
authors.forename: Akiyo
authors.initials: A
authors.lastname: Koshiyama
authors.forename: Taiki
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Hiroko
authors.initials: H
authors.lastname: Sugawara
authors.forename: Fumika N
authors.initials: FN
authors.lastname: Hamada
authors.forename: Satoshi H
authors.initials: SH
authors.lastname: Namekawa
authors.forename: Satomi
authors.initials: S
authors.lastname: Ishii
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishizaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Chiku
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nara
authors.forename: Kengo
authors.initials: K
authors.lastname: Sakaguchi
mesh_terms: D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D002467:Cell Nucleus / Q000737:chemistry / Q000201:enzymology; D003302:Coprinus / Q000201:enzymology; D004250:DNA Topoisomerases, Type II / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D047468:Immunoprecipitation; D008540:Meiosis; D008969:Molecular Sequence Data; D017384:Sequence Deletion; D020798:Two-Hybrid System Techniques
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D004250:DNA Topoisomerases, Type II