Functions as a guanine nucleotide exchange factor (GEF) activating either RalA or RalB GTPases and plays an important role in intracellular transport. Interacts and acts as an effector molecule for R-Ras, H-Ras, K-Ras, and Rap (By similarity). During bacterial clearance, recognizes 'Lys-33'-linked polyubiquitinated TRAF3 and subsequently mediates assembly of the exocyst complex .
Subcellular locations: Cytoplasm, Nucleus
Localizes mainly in the peripheral region of the cytoplasmic membrane in oocytes and in preimplantation embryos until the 8-cell stage. Between the late 1-cell and the early 2-cell stages, nuclear localization becomes stronger. After the 4-cell stage, not detected in the nucleus.