title: Regulation of cytokinesis by mgcRacGAP in B lymphocytes is independent of GAP activity.
abstract: In cytokinesis, several molecules including small G proteins and their regulators are known to have important roles. One of these regulators, mgcRacGAP has GTPase activating protein (GAP) activity for Rac, Cdc42 and Rho. MgcRacGAP has also been shown to be involved in cytokinesis using various cell types. However, the requirement of mgcRacGAP for cytokinesis and survival in B lymphocytes has not been fully examined. Here, we demonstrate that normal cytokinesis in B lymphocytes requires the GAP and NH2 terminal domains but not GAP activity of mgcRacGAP. In addition, we report that apoptosis induced by conditional ablation of mgcRacGAP in the B cell line is fully rescued by the introduction of a GAP-inactive mutant, suggesting that the survival defect in mgcRacGAP-deficient B cells is also independent of GAP activity.
authors.affiliation: Department of Molecular Genetics, Institute for Liver Research, Kansai Medical University, Fumizono-cho 10-15, Moriguchi, Osaka 570-8506, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yamada
authors.forename: Masaki
authors.initials: M
authors.lastname: Hikida
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kurosaki
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000378:metabolism; D017209:Apoptosis; D001402:B-Lymphocytes / Q000166:cytology / Q000201:enzymology / Q000502:physiology*; D002453:Cell Cycle / Q000502:physiology*; D002460:Cell Line; D002470:Cell Survival; D002645:Chickens; D048749:Cytokinesis / Q000502:physiology*; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D015739:Nocodazole / Q000378:metabolism; D017434:Protein Structure, Tertiary
chemical_list: D000970:Antineoplastic Agents; D020690:GTPase-Activating Proteins; C115995:mgcRacGAP; D015739:Nocodazole