InterPro domain: IPR003377

This entry represents a group of conserved proteins from fungi, plants to animals. They are transmembrane proteins. Proteins in this entry include budding yeast Erv14/15, Drosophila Cornichon and human CNIH1/2/3/4.

The drosophila cornichon protein (gene: cni), the founding member of this family, is an integral component of the COPII-coated vesicles that mediate cargo export from the yeast endoplasmic reticulum (ER) [ 1 ]. It is required in the germline for dorsal-ventral signalling. The dorsal-ventral pattern formation involves a reorganisation of the microtubule network correlated with the movement of the oocyte nucleus, and depending on the initial correct establishment of the anterior-posterior axis via a signal from the oocyte produced by cornichon and gurken and received by torpedo protein in the follicle cells [ 2 ].

Erv14 is a COPII-coated vesicle protein involved in vesicle formation and incorporation of specific secretory cargo. It is required for axial budding [ 3 , 4 ].

CNIH1 is involved in the selective transport and maturation of TGF-alpha family proteins [ 5 ].

1. Drosophila Cornichon acts as cargo receptor for ER export of the TGFalpha-like growth factor Gurken. Development 133, 459-70
2. cornichon and the EGF receptor signaling process are necessary for both anterior-posterior and dorsal-ventral pattern formation in Drosophila. Cell 81, 967-78
3. Transport of axl2p depends on erv14p, an ER-vesicle protein related to the Drosophila cornichon gene product. J. Cell Biol. 142, 1209-22
4. Erv14 family cargo receptors are necessary for ER exit during sporulation in Saccharomyces cerevisiae. J. Cell. Sci. 120, 908-16
5. Cornichon regulates transport and secretion of TGFalpha-related proteins in metazoan cells. J. Cell. Sci. 120, 2454-66