title: GTP binding is required for SEPT12 to form filaments and to interact with SEPT11.
abstract: Septins are a family of filament-forming GTP-binding proteins involved in a variety of cellular process such as cytokinesis, exocytosis, and membrane dynamics. Here we report the biochemical and immunocytochemical characterization of a recently identified mammalian septin, SEPT12. SEPT12 binds GTP in vitro, and a mutation (Gly56 to Asn) in the GTP-binding motif abolished binding. Immunocytochemical analysis revealed that wild-type SEPT12 formed filamentous structures when transiently expressed in Hela cells whereas SEPT12G56A generated large aggregates. In addition, wild-type SEPT12 failed to form filaments when coexpressed with SEPT12G56A. We also observed that GTP-binding by SEPT12 is required for interaction with SEPT11 but not with itself.
authors.affiliation: State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, PR China.
authors.forename: Xiangming
authors.initials: X
authors.lastname: Ding
authors.forename: Wenbo
authors.initials: W
authors.lastname: Yu
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: ShuQing
authors.initials: S
authors.lastname: Shen
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.forename: Lihuan
authors.initials: L
authors.lastname: Cao
authors.forename: Bo
authors.initials: B
authors.lastname: Wan
authors.forename: Long
authors.initials: L
authors.lastname: Yu
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D006160:Guanosine Triphosphate / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D009154:Mutation; D058112:Septins
chemical_list: D018797:Cell Cycle Proteins; D006160:Guanosine Triphosphate; D019204:GTP-Binding Proteins; C496549:SEPTIN11 protein, human; C502729:SEPTIN12 protein, human; D058112:Septins