required to specify ventral cell neural patterning. loss of function of cyclops or oep in zebrafish results in cyclopic embryos characterized by a lack of medial floor plate and ventral forebrain. not all nodals result in the formation of mesoectoderm. xenopus nodal related 3, (xnr3) a divergent member of the tgfβ superfamily, induces the expression of the protein, xbra. the xbra expression pattern, in correlation the expression pattern another neuroinducer, xlim-1, result in the patterning of the organizer in xenopus. this signaling in conjuncture with other nodals, noggin, chordin, follistatin and others results in the final patterning of vertebrate central nervous system.