Hypothetical protein KIAA0079 is a mammalian homologue of yeast Sec24p

The Sec23p-Sec24p complex is a component of COPII-coated vesicles that mediate protein transport from the endoplasmic reticulum in yeast. The mammalian hypothetical protein KIAA0079 (KIAA0079p) exhibits sequence similarity to yeast Sec24p. KIAA0079p was co-eluted with mammalian Sec23p on gel filtration. In vitro binding experiments revealed that the C-terminal region of KIAA0079p binds to the N-terminal region of mammalian Sec23p. Overexpression of KIAA0079p caused a defect in protein export from the endoplasmic reticulum. These results support the idea that KIAA0079p is a functional homologue of yeast Sec24p.