title: Two Geminin homologs regulate DNA replication in silkworm, Bombyx mori.
abstract: DNA replication is rigorously controlled in cells to ensure that the genome duplicates exactly once per cell cycle. Geminin is a small nucleoprotein, which prevents DNA rereplication by directly binding to and inhibiting the DNA replication licensing factor, Cdt1. In this study, we have identified 2 Geminin genes, BmGeminin1 and BmGeminn2, in silkworm, Bombyx mori. These genes contain the Geminin conserved coiled-coil domain and are periodically localized in the nucleus during the S-G2 phase but are degraded at anaphase in mitosis. Both BmGeminin1 and BmGeminin2 are able to homodimerize and interact with BmCdt1 in cells. In addition, BmGeminin1 and BmGeminin2 can interact with each other. Overexpression of BmGeminin1 affects cell cycle progression: cell cycle is arrested in S phase, and RNA interference of BmGeminin1 leads to rereplication. In contrast, overexpression or knockdown of BmGeminin2 with RNAi did not significantly affect cell cycle, while more rereplication occurred when BmGeminin1 and BmGeminin2 together were knocked down in cells than when only BmGeminin1 was knocked down. These data suggest that both BmGeminin1 and BmGeminin2 are involved in the regulation of DNA replication. These findings provide insight into the function of Geminin and contribute to our understanding of the regulation mechanism of cell cycle in silkworm.
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.
authors.forename: Xiao-Fang
authors.initials: XF
authors.lastname: Tang
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|b Basic Medical School , Guiyang College of Traditional Chinese Medicine , Guiyang , China.
authors.forename: Xiang-Yun
authors.initials: XY
authors.lastname: Chen
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|c Department of Biochemistry and Molecular Biology , Chongqing Medical University , Chongqing , China.
authors.forename: Chun-Dong
authors.initials: CD
authors.lastname: Zhang
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|b Basic Medical School , Guiyang College of Traditional Chinese Medicine , Guiyang , China.
authors.forename: Yao-Feng
authors.initials: YF
authors.lastname: Li
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.
authors.forename: Tai-Hang
authors.initials: TH
authors.lastname: Liu
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Zhou
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.
authors.forename: La
authors.lastname: Wang
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|d Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry , Southwest University , Chongqing , China.
authors.forename: Peng
authors.initials: P
authors.lastname: Chen
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|d Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry , Southwest University , Chongqing , China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Lu
authors.affiliation: a State Key Laboratory of Silkworm Genome Biology , Southwest University , Chongqing , China.|d Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry , Southwest University , Chongqing , China.
authors.forename: Min-Hui
authors.initials: MH
authors.lastname: Pan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000378:metabolism*; D002453:Cell Cycle; D004261:DNA Replication; D064248:Geminin / Q000737:chemistry* / Q000378:metabolism*; D019476:Insect Proteins / Q000737:chemistry* / Q000378:metabolism*; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D010802:Phylogeny; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid
chemical_list: D064248:Geminin; D019476:Insect Proteins; D009687:Nuclear Proteins
keywords: Bombyx mori; Cdt1; DNA replication; Geminin; cell cycle