Acts upstream of or within several processes, including Kupffer's vesicle development; regionalization; and regulation of fibroblast growth factor receptor signaling pathway. Located in endoplasmic reticulum. Is expressed in several structures, including forerunner cell group; margin; midbrain hindbrain boundary; midbrain hindbrain boundary neural rod; and polster. Orthologous to human CNPY1 (canopy FGF signaling regulator 1).