DOCK family members are evolutionarily conserved guanine nucleotide exchange factors (GEFs) for Rho-family GTPases []. DOCK proteins are required during several cellular processes, such as cell motility and phagocytosis. The N-terminal SH3 domain of the DOCK proteins functions as an inhibitor of GEF, which can be relieved upon its binding to the ELMO1-3 adaptor proteins, after their binding to active RhoG at the plasma membrane [, ]. DOCK family proteins are categorised into four subfamilies based on their sequence homology: DOCK-A subfamily (DOCK1/180, 2, 5), DOCK-B subfamily (DOCK3, 4), DOCK-C subfamily (DOCK6, 7, 8), DOCK-D subfamily (DOCK9, 10, 11) []. This entry represents DOCK2 (dedicator of cytokinesis 2). DOCK2 is involved in cytoskeletal rearrangements required for lymphocyte migration in response of chemokines. It activates RAC1 and RAC2, but not CDC42, by functioning as a guanine nucleotide exchange factor (GEF), which exchanges bound GDP for free GTP. It may also participate in IL2 transcriptional activation via the activation of RAC2 [].
