RanisamemberoftheRasfamilyofsmallGTPases.Ranisanimportantcomponentofmanycrucialnucleocytoplasmictransportpathways.ThecyclingofRaniscontrolledbytheRanGTP-RanGDPgrADIentestablishedbytheRanGuaninenucleotideexchangeFactor(RanGEF)RCC1andtheRanGTPase-activatingProtein(RanGAP).ThesetwoproteinscombinetocreateaRangradientwhereRanGDPispredominantlycytoplasmic.RCC1bindstochromatinandsoRanGTPisfoundassociatedwithDNA.RCC1dissociatedGDPfromRanandallowsGTPtobebound.AsRanleavesthenucleusThetwoRanbindingproteins,RanBP1andRanBP2cooperatewithRanGAPtoinduceGTPhydrolysisofRan.ThereareseveralnuclearimportfactorsthatusetheRangradientaspartoftheirtranslocationmechanism

Contributor:

REFERENCES:KuerstenS,OhnoM,MattajIW.Nucleocytoplasmictransport:Ran,betaandbeyond.TrendsCellBiol.2001Dec;11(12):497-503.Review.