Proteins of the IQGAP family have been identified as candidate effectors for the Rho family of GTPases.
The domain structure of IQGAP family members suggests that these proteins may function as regulators of the cytoskeleton.
In particular their sequences include 1) an actin-binding domain homologous to that found in calponin, 2) IQ motifs for interaction with calmodulin and 3) a GTPase-binding domain.
Two IQGAP isoforms have been identified, IQGAP1 and IQGAP2.
These proteins share 62% sequence identity.
The 189kD IQGAP1 protein exhibits a broad tissue distribution and is especially enriched in placenta, lung, and kidney.
On the other hand, the 180kD IQGAP2 protein is restricted in its tissue distribution and appears to be expressed exclusively in liver.
Both IQGAP1 and IQGAP2 bind to GTP-bound Cdc42 and inhibit the rate of GTP hydrolysis.
Applications:Suitable for use in Western Blot and Immunoprecipitation.
Other applications not tested.
Recommended Dilutions:Western Blot: 1-2ug/ml detects IQGAP1 from a HepG2 RIPA cell lysate.
HepG2 cell lysate was resolved by electrophoresis, transferred to PVDF and probed with I8448-75.
Proteins were visualized using an IgG (HRP) Gt x Mo and a chemiluminescence detection system.
Immunoprecipitation: 4ug immunoprecipitated IQGAP1 from 500ug of a HepG2 RIPA lysate.
Optimal dilutions to be determined by the researcher.
