When ELMO1 is complexed with DOCK180, Rac GTPase-dependent biological processes are activated. The pH domain of ELMO1 functions in trans to stabilize DOCK180 and make it resistant to degradation. When ELMO1 binds to DOCK180 it relieves the steric inhibition of DOCK180 which then activates the Rac GTPase. The pro-rich motif of the C terminus on ELMO1 is essential for the binding of ELMO1 to the SH3 domain at the N terminus of DOCK180. The complex of ELMO1 and DOCK180 act as a regulator of Rac during development of a cell and cell migration. Mutation of both interaction sites for DOCK180 on ELMO1 will lead to the disruption of the ELMO1-DOCK180 complex. ELMO1 complexed with both DOCK180 and CrkII leads to maximal efficiency of phagocytosis in the cell. This complex of molecules happens upstream of Rac during phagocytosis.
