title: The Rif GTPase regulates cytoskeletal signaling from plexinA4 to promote neurite retraction.
abstract: The small GTPase Rif is required for the early stages of dendritic spine formation in neurons, acting through the formin mDia2 to control actin polymerization. Rif is expressed at high levels in the brain, suggesting broader roles in neuronal function. We screened a yeast two-hybrid cDNA library to identify additional binding partners for Rif of potential relevance to neuronal function. We found that Rif interacts with FARP1, a neuronal activator of the RhoA GTPase. We show that Rif has two separate roles in FARP1 regulation-in controlling its association with plexinA4, and in releasing active RhoA from a plexinA4/FARP1 complex. The regulation of FARP1 by Rif promotes neurite retraction in cells stimulated with the semaphorin Sema6A.
authors: College of Life Sciences, Inner Mongolia University, University Road, Hohhot, China.
authors: Lifei
authors: L
authors: Fan
authors: College of Life Sciences, Inner Mongolia University, University Road, Hohhot, China.
authors: Huijuan
authors: H
authors: Yan
authors: School of Biochemistry, Medical Sciences Building, University Walk, University of Bristol, Bristol, UK.
authors: Stephanie
authors: S
authors: Pellegrin
authors: College of Life Sciences, Inner Mongolia University, University Road, Hohhot, China. Electronic address: morigenm@hotmail.com.
authors: Morigen
authors: School of Biochemistry, Medical Sciences Building, University Walk, University of Bristol, Bristol, UK. Electronic address: h.mellor@bristol.ac.uk.
authors: Harry
authors: H
authors: Mellor
mesh_terms: D000818:Animals; D003599:Cytoskeleton / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D019169:Jurkat Cells; D016501:Neurites / Q000502:physiology*; D016716:PC12 Cells; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D039961:Semaphorins / Q000378:metabolism; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: C524474:Plxna4 protein, human; D011956:Receptors, Cell Surface; C504201:SEMA6A protein, human; D039961:Semaphorins; C419867:RHOF protein, human; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein
keywords: Actin; Neurite outgrowth; Plexin; Rho GTPases; Semaphorin