Rac1B is an alternatively spliced form of Rac1 gene.
Rac1B does not lead to lamellipodia formation, or the activation of PAK1, AKT1, or c-Jun-NH2- kinase activities.
However, Rac1B retains the ability to stimulate the NF-kappa-B pathway.
MMP3 can induce the expression of RACB1.
RACB1 increases the cellular levels of ROS, causing an upregulation of Snail and induction of EMT.