Background:  

    RAC1b, also named as TC25, belongs to the small GTPase superfamily and Rho family. RAC1 is a plasma 

    membrane-associated small GTPase which cycles between active GTP-bound and inactive GDP-bound states. 

    In its active state, it binds to a variety of effector proteins to regulate cellular responses such as secretory 

    processes, phagocytosis of apoptotic cells, epithelial cell polarization and growth-factor induced formation of 

    membrane ruffles.