Table 1 Platelet Rho GTPase effectors

A list of known effector proteins for RhoA, Rac1 and Cdc42 compiled from Bishop and Hall [113] and Bustelo et al. [144] and cross-referenced against mRNA transcripts from human platelets [35], and two recent proteomic databases such that only proteins known to be expressed are listed [145,146].

EffectorProtein type (alternate protein name)Upstream GTPaseMain biological function
FilaminAActin binding proteinRhoA, Rac1, Cdc42Cytoskeletal regulation, actin filament cross-linking
CopG2Coatomer protein (γ2-Cop)Cdc42Vesicle trafficking (clathrin route)
DIAPH1,2ForminRhoA, Rac1Cytoskeletal change via profilin and IRSp53
FHOD1ForminRac1Cytoskeletal and transcriptional regulation
FMNL1ForminRac1Cytoskeletal organization, cell polarity, cytokinesis
IP3R1Inositol 1,4,5-triphosphate receptorRhoACalcium entry in endothelial cells
PI4,5PKLipid kinaseRhoAPhosphatidylinositol bisphosphate level modulation
CybANADPH oxidase complex subunitRac1Superoxide production
NCF1,2NADPH oxidase complex subunitRac1, Cdc42Superoxide production
PLC-β2Phospholipase, C type (PLC-β2)Cdc42, Rac1Production of second messengers
KCNA2Potassium Channel subunitRhoAPotassium entry
PIK3R1Regulatory p85 subunit of PIK3CRac1, Cdc42Regulation of PIK3C activity, signal transduction
PPP1R12ARegulatory subunit of phosphatase1RhoAMLC inactivation, cytoskeletal regulation
IQGAP1,2RhoGAP and scaffold proteinRac1, Cdc42Cytoskeletal regulation, cell–cell contacts
ARFIP2Scaffold protein (Por1)Rac1Cytoskeletal regulation
Cdc42SE1,2Scaffold protein (Spec1,2)Rac1, Cdc42Modulation of GTPase signalling outputs
CYFIP1,2Scaffold protein (Pir121)Rac1Regulation of the cytoskeleton via WASF proteins
MTSS1Scaffold proteinRac1Cytoskeletal organization via WASF/WAVE
Kinectin1Scaffold proteinRhoA, Rac1, Cdc42Kinesin binding, microtubule vesicular trafficking
NCK1Scaffold protein with SH2/3 domainsRac1Complex formation with WASP, signal transduction
NCKAP1Scaffold protein (Nap125, Nap1)Rac1Regulation of the cytoskeleton via WASF proteins
N-WASPScaffold proteinCdc42Cytoskeletal regulation via Arp2/3 complex
Pard6 A,GScaffold protein (Par6α,γ)Rac1, Cdc42Cell polarity. Links GTPases and atypical PKCs
Trip10Scaffold proteinCdc42Binding of WASP to microtubules
WASPScaffold proteinRac1Cytoskeletal regulation via the Arp2/3 complex
WAVE/Scar1,2Scaffold proteinCdc42, Rac1Cytoskeletal regulation via the Arp2/3 complex
Cdc42bpgBSerine/threonine kinase (MRCKβ)Rac1, Cdc42Cytoskeletal regulation
p70S6KSerine/threonine kinaseCdc42Regulation of translation, cell cycle
PAK2Serine/threonine kinaseRac1, Cdc42Cytoskeletal organization, kinase activation
PKCαSerine/threonine kinaseRhoA, Rac1, Cdc42Signal transduction
PKN1,2Serine/threonine kinase (Prk)RhoAVesicle recycling, PLD1 activation
ROCK1,2Serine/threonine kinase (Rok α,β)RhoACytoskeleton, blockage of cell contact inhibition
Stat3Transcriptional factorRac1, Cdc42Transcription
α-Tubulin-1CTubulinRac1Integral component of microtubules