Cytokine that may play a role in the development of the medial pallium and during optic nerve and pecten development by modulating BMP signaling. In brain first detected at E6 and persisted until E14. On E10 brain, expressed in the dorsal region of the telencephalic hemispheres and cells located in the ventral diencephalon. On E14 head, expressed in the meninges of the spinal cord. Expressed in the developing optic nerve and at the optic nerve/pecten junction. Belongs to the DAN family.