GTP binding is required for SEPT12 to form filaments and to interact with SEPT11.
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.
Ding
Xiangming
X
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, PR China.
Yu
Wenbo
W
Liu
Ming
M
Shen
ShuQing
S
Chen
Fang
F
Cao
Lihuan
L
Wan
Bo
B
Yu
Long
L
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
D018797:Cell Cycle Proteins; D006160:Guanosine Triphosphate; D019204:GTP-Binding Proteins; C496549:SEPTIN11 protein, human; C502729:SEPTIN12 protein, human; D058112:Septins