Selective cargo export from the endoplasmic reticulum is brought about by the budding of COPII vesicles. While the main structural components of the COPII coat have been identified and characterized, the regulatory event(s) promoting COPII vesicle biogenesis and cargo selection still remains largely unknown. New data by Glick and colleagues suggest that Sec12 and COPII function may be downstream of important early events coordinated by transitional ER (tER) exit sites.
The Scripps Research Institute, Department of Cell, and The Institute for Childhood and Neglected Disease, 10550 N. Torrey Pines Road, La Jolla, CA 92130, USA.
