The function of TIAM1 (TIAM Rac1 associated GEF 1, Ensembl gene identifier ENSG00000156299) is as follows. Guanyl-nucleotide exchange factor that activates RHO-like proteins and connects extracellular signals to cytoskeletal activities. Activates RAC1, CDC42, and to a lesser extent RHOA and their downstream signaling to regulate processes like cell adhesion and cell migration. .