G-Protein Coupled Receptors (GPCR) sense extracellular signals and activate different Guanine nucleotide binding proteins (G-proteins) that have alpha, beta and gamma subunits. Upon activation, the alpha subunit of G-proteins dissociates from beta-gamma and the both are then free to regulate downstream effectors. Serine/threonine-protein kinase PAK 1 can directly bind with Rho guanine nucleotide exchange factor 6 (ARHGEF6, PIX-Alpha) in the cytosol. This complex is then translocated to the plasma membrane where Cell division control protein 42 homolog (CDC42) is activated. CDC42 is known to be involved in epithelial cell polarization processes.