Involved in vesicular trafficking at the Golgi apparatus level. Involved in endosome-to-Golgi trafficking. Interacts with RAB6A (By similarity). Directly interacts with TBC1D23 (PubMed:29084197). Interacts with FAM91A1; this interaction may be mediated by TBC1D23 (Probable). Present in the acrosome of spermatids up to the late cap-stage, but not in mature spermatozoa. Extended rod-like protein with coiled-coil domains.