title: GTPases and T cell activation.
abstract: Guanine nucleotide binding proteins rapidly cycle between a guanosine diphosphate (GDP)-bound and guanosine triphosphate (GTP)-bound state, and they operate as binary switches that control cell activation in response to environmental cues. GTPases adopt different conformations when binding GTP vs. GDP. The GTP-bound state is generally considered to be the active conformation that allows GTPases to interact with downstream effectors and thereby initiate downstream signaling pathways, which regulate many important biological processes. Many members of the Ras family of GTPases, notably Ras and Rap1A, and the Rho family GTPases, Cdc42Hs, Rac1, Rac2 and RhoA, are important components of signal transduction pathways used by antigen receptors, costimulatory, cytokine and chemokine receptors to regulate the immune response. This review discusses current knowledge and ideas about the regulation and function of these GTPases in lymphocytes.
authors.affiliation: Division of Cell Biology and Immunology, School of Life Sciences, MSI/WTB Complex, University of Dundee, Dundee, UK. doreen.cantrell@ancer.org.uk
authors.forename: Doreen Ann
authors.initials: DA
authors.lastname: Cantrell
mesh_terms: D000818:Animals; D020690:GTPase-Activating Proteins / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D020559:Monomeric GTP-Binding Proteins / Q000502:physiology*; D011494:Protein Kinases / Q000378:metabolism; D013601:T-Lymphocytes / Q000201:enzymology* / Q000276:immunology; D018631:ras Proteins / Q000378:metabolism
chemical_list: D020690:GTPase-Activating Proteins; C085379:rho GTPase-activating protein; D011494:Protein Kinases; C099264:RAP kinase; D020559:Monomeric GTP-Binding Proteins; D018631:ras Proteins