title: The RacGAP protein FilGAP is a negative regulator of chemokine-promoted lymphocyte migration.
abstract: Rho family small GTPases regulate lymphocyte migration induced by chemokines. However, how lymphocyte migration is regulated by Rho GTPases remains to be elucidated. Here, we identified FilGAP, a Rac-specific GAP, as a negative regulator of lymphocyte polarization and migration. Depletion of FilGAP in mouse pro-B BAF cells increased cellular elongation and membrane protrusion after stimulation of the cells with SDF-1α, which caused increased migration speed. Although FilGAP is detectable both at the front and rear of polarized cells, FilGAP appears to be concentrated at the tip of retracting lamellae of moving lymphocytes. Moreover, depletion of FilGAP increased activation of Rac at the front of polarized cells. Thus, FilGAP may inhibit lamellae extension at the front of moving lymphocytes.
authors.affiliation: Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, Sagamihara, Kanagawa, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Iida
authors.affiliation: Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, Sagamihara, Kanagawa, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Saito
authors.affiliation: Division of Immunology, Department of Biosciences, School of Science, Kitasato University, Sagamihara, Kanagawa, Japan.
authors.forename: Koko
authors.initials: K
authors.lastname: Katagiri
authors.affiliation: Department of Molecular Genetics, Institute of Biomedical Science, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kinashi
authors.affiliation: Division of Cell Biology, Department of Biosciences, School of Science, Kitasato University, Sagamihara, Kanagawa, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Ohta
mesh_terms: D000818:Animals; D002460:Cell Line; D016764:Cell Polarity; D054377:Chemokine CXCL12 / Q000378:metabolism*; D002633:Chemotaxis; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008214:Lymphocytes / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D020744:rac GTP-Binding Proteins / Q000378:metabolism
chemical_list: C497034:ARHGAP24 protein, mouse; D054377:Chemokine CXCL12; C515256:Cxcl12 protein, mouse; D020690:GTPase-Activating Proteins; D020744:rac GTP-Binding Proteins
keywords: Rac; Rho; cell adhesion; cell migration; cell polarity; chemotaxis; signal transduction; small GTPases