The novel Rho-family GTPase rif regulates coordinated actin-based membrane rearrangements.
Small GTPases of the Rho family have a critical role in controlling cell morphology, motility and adhesion through dynamic regulation of the actin cytoskeleton [1,2]. Individual Rho GTPases have been shown to regulate distinct components of the cytoskeletal architecture; RhoA stimulates the bundling of actin filaments into stress fibres [3], Rac reorganises actin to produce membrane sheets or lamellipodia [4] and Cdc42 causes the formation of thin, actin-rich surface projections called filopodia [5]. We have isolated a new Rho-family GTPase, Rif (Rho in filopodia), and shown that it represents an alternative signalling route to the generation of filopodial structures. Coordinated regulation of Rho-family GTPases can be used to generate more complicated actin rearrangements, such as those underlying cell migration [6]. In addition to inducing filopodia, Rif functions cooperatively with Cdc42 and Rac to generate additional structures, increasing the diversity of actin-based morphology.
Ellis
S
S
Department of Biochemistry, School of Medical Sciences, University of Bristol, Bristol, UK.
Mellor
H
H
D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism*; D048429:Cell Size; D015638:Cytochalasin D / Q000494:pharmacology; D003598:Cytoskeletal Proteins / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000378:metabolism; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009154:Mutation; D011554:Pseudopodia / Q000187:drug effects / Q000378:metabolism*; D016415:Sequence Alignment; D013997:Time Factors; D016596:Vinculin / Q000276:immunology; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism; D020744:rac GTP-Binding Proteins / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D000199:Actins; D003598:Cytoskeletal Proteins; D008164:Luminescent Proteins; D016596:Vinculin; D049452:Green Fluorescent Proteins; D015638:Cytochalasin D; C419867:RHOF protein, human; D020764:cdc42 GTP-Binding Protein; D020744:rac GTP-Binding Proteins; D020741:rho GTP-Binding Proteins