Has anyone used G-LISA or similar RhoA/Rac1/Cdc42 GTPase pulldown assays for analysis of murine whole organ lysates? It could theoretically work, but has anyone tried this?
We successfully pulled down active Rac from tumour explants using the CRIB domain of PAK1 as a bait.
However, it is essential to use only fresh material as frozen samples do not preserve genuine Rac-GTP levels and flatten any difference due to treatment (and/or genotype).