Table 1.

Cellular localizations implicated in the cytoskeletal functions of IQGAP proteins

Organism and IQGAP proteins	Cellular localizations	Proposed cytoskeletal functions	References
Saccharomyces cerevisiae
Iqg1/Cyk1	Bud neck Actomyosin ring	Cytokinesis and cell polarity Cytokinesis	Osman & Cerione, 1998 Shannon & Li, 1999
Schizosaccharomyces pombe
Rng2	Actomyosin ring	Cytokinesis	Eng et al, 1998
Dictyostelium discoideum
DGAP1	Cell cortex, cleavage furrow	Cytokinesis	Faix et al, 2001
Xenopus laevis
XIQGAP1	Filopodia, lamellipodia, cell–cell contacts	Cell migration	Yamashiro et al, 2003
XIQGAP2	Nucleus, adherens junctions	E-cadherin-mediated cell–cell contacts	Yamashiro et al, 2003, 2007
Mammalian
IQGAP1	Lamellipodia Adherens junctions Leading front Pseudopodia Phagocytic cup	Actin crosslinking/bundling E-cadherin-mediated cell–cell contacts Microtubule capture, polarity Cell motility, invasion Phagocytosis	Bashour et al, 1997 Kuroda et al, 1998 Fukata et al, 2002 Jia et al, 2005 Brandt et al, 2007
IQGAP2	Filopodia, lamellipodia	Platelet aggregation	Schmidt et al, 2003
IQGAP3	Tip of axons	Axon elongation	Wang et al, 2007

IQGAPs, proteins containing calmodulin-binding IQ motifs and with homology to GTPase activating proteins (GAPs).