Prevents ENO1-mediated transcriptional repression and antagonizes ENO1-mediated cell death. May play a role in vesicular transport from endoplasmic reticulum to Golgi (By similarity). Part of the multisubunit TRAPP (transport protein particle) complex. Interacts with ENO1, PITX1, SF1, TRAPPC2L and TRAPPC3. Localized in perinuclear granular structures. Belongs to the TRAPP small subunits family. Sedlin subfamily.