title: Formin-mediated epigenetic maintenance of centromere identity.
abstract: Accurate chromosome segregation in mammalian cells is guided by the centromere, a specialized chromosome region defined by the histone H3 variant centromere protein A (CENP-A). It is not well understood how cells maintain CENP-A levels at centromeres while continuously going through genome replications and cell divisions. A MgcRacGAP-dependent small GTPase molecular switch has been shown as essential for centromeric CENP-A maintenance. By using quantitative imaging, pulse-chase and live cell analysis, a recent work has suggested that the diaphanous formin mDia2, a well-established small GTPase effector, functions downstream of this small GTPase pathway to maintain CENP-A levels at centromeres. A constitutively active mDia2 construct is able to rescue the CENP-A loading defect caused by MgcRacGAP depletion. This study has uncovered an unsuspected role of the cytoskeleton protein mDia2 as an effector of the MgcRacGAP-dependent small GTPase signaling inside the nucleus to participate in the epigenetic regulation of centromere maintenance during cell cycle.
authors.affiliation: a Department of Pathology and Cell Biology , Columbia University Medical Center , New York , NY , USA.
authors.forename: Chenshu
authors.initials: C
authors.lastname: Liu
authors.affiliation: a Department of Pathology and Cell Biology , Columbia University Medical Center , New York , NY , USA.
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Mao
mesh_terms: D000818:Animals; D002503:Centromere / Q000235:genetics*; D044127:Epigenesis, Genetic; D006801:Humans; D008840:Microfilament Proteins / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D008840:Microfilament Proteins; D009707:Nucleosomes; D020741:rho GTP-Binding Proteins
keywords: CENP-A; MgcRacGAP; cell cycle; centromere; cytoskeleton; diaphanous formin; epigenetics; mDia2