Component of the coat protein complex II (COPII) which promotes the formation of transport vesicles from the endoplasmic reticulum (ER). The coat has two main functions, the physical deformation of the endoplasmic reticulum membrane into vesicles and the selection of cargo molecules. It also functions as a component of the nuclear pore complex (NPC). NPC components, collectively referred to as nucleoporins (NUPs), can play the role of both NPC structural components and of docking or interaction partners for transiently associated nuclear transport factors. SEC13 is required for efficient mRNA export from the nucleus to the cytoplasm and for correct nuclear pore biogenesis and distribution. As a component of the GATOR complex may function in the amino acid-sensing branch of the TORC1 signaling pathway. Component of the COPII coat composed of at least 5 proteins: the sec23/24 complex, the sec13/31 complex, and the protein sar1A or sar1B. Component of the nuclear pore complex (NPC) which constitutes the exclusive means of nucleocytoplasmic transport. Probably part of the GATOR complex. Present with 21400 molecules/cell in log phase SD medium. Belongs to the WD repeat SEC13 family.