This gene encodes a member of the Rho-guanine nucleotide exchange factor (Rho-GEF) family. These proteins regulate Rho GTPases by catalyzing the exchange of GDP for GTP. The encoded protein specifically activates RhoG and plays a role in the promotion of macropinocytosis. Underexpression of the encoded protein may be a predictive marker of chemoresistant disease. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Oct 2011].