Filament-forming cytoskeletal GTPase (By similarity). May play a role in cytokinesis (Potential). May play a role in the internalization of 2 intracellular microbial pathogens, Listeria monocytogenes and Shigella flexneri. . This is the function of SEPTIN9 (septin 9, Ensembl gene identifier ENSG00000184640).