Canopy 1 Homolog (CNPY1)

Cnpy1 is expressed in the midbrain-hindbrain (MHB) boundary in zebrafish, binds FGFR1, and plays a role in FGF signaling. Searches of sequence databases revealed that the deduced zebrafish protein is widely conserved and shares similarity with putative orthologs in human, mouse, Xenopus laevis, chick, and medaka.

The human CNPY1 gene encodes a 186-amino acid protein. Cnpy1 contains a putative endoplasmic reticulum (ER) retention signal, HSEL, that differs from the consensus ER retention signal KDEL. Morpholino oligonucleotide inhibition of cnpy1 in zebrafish embryos resulted in defects in the MHB, otic vesicles, and tail bud and demonstrated that cnpy1 is required for maintenance of the MHB.cnpy1 binds the extracellular domain of FGFR1 and also binds ActRII , albeit to a lesser degree.