title: Analysis of the small GTPase gene superfamily of Arabidopsis.
abstract: Small GTP-binding proteins regulate diverse processes in eukaryotic cells such as signal transduction, cell proliferation, cytoskeletal organization, and intracellular membrane trafficking. These proteins function as molecular switches that cycle between "active" and "inactive" states, and this cycle is linked to the binding and hydrolysis of GTP. The Arabidopsis genome contains 93 genes that encode small GTP-binding protein homologs. Phylogenetic analysis of these genes shows that plants contain Rab, Rho, Arf, and Ran GTPases, but no Ras GTPases. We have assembled complete lists of these small GTPases families, as well as accessory proteins that control their activity, and review what is known of the functions of individual members of these families in Arabidopsis. We also discuss the possible roles of these GTPases in relation to their similarity to orthologs with known functions and localizations in yeast and/or animal systems.
authors.affiliation: Center for Plant Cell Biology and Department of Botany and Plant Sciences, University of California, Riverside, California 92521, USA.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Vernoud
authors.forename: Amy C
authors.initials: AC
authors.lastname: Horton
authors.forename: Zhenbiao
authors.initials: Z
authors.lastname: Yang
authors.forename: Erik
authors.initials: E
authors.lastname: Nielsen
mesh_terms: D020727:ADP-Ribosylation Factors / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics*; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics*; D005810:Multigene Family / Q000235:genetics; D010802:Phylogeny; D015398:Signal Transduction / Q000235:genetics; D020691:rab GTP-Binding Proteins / Q000235:genetics; D020931:ran GTP-Binding Protein / Q000235:genetics; D020741:rho GTP-Binding Proteins / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D020727:ADP-Ribosylation Factors; D020559:Monomeric GTP-Binding Proteins; D020691:rab GTP-Binding Proteins; D020931:ran GTP-Binding Protein; D020741:rho GTP-Binding Proteins