Nodal coreceptor involved in the correct establishment of the left-right axis. May play a role in mesoderm and/or neural patterning during gastrulation. No expressed in adult tissues. Expressed during gastrulation (from 6.5 dpc to 11 dpc) in two spatial domains that correspond to the axial and lateral mesoderm. In the first domain expression is progressively localized to the anterior primitive streak, the head process, and the node and notochordal. In the second domain, expression is initially concentrated in the lateral region of the egg cylinder, and is later found circumferentially in the intermediate and lateral plate mesoderm. Furthermore, the expression can also be detected at the early head-fold stage in the midline neuroectoderm, and consequently is an early marker for the prospective floor plate of the neural tube. Expression ceases at the end of gastrulation, and has not been observed in later embryonic stages. N-glycosylated. Positional defects in internal organs. The lung presents a right pulmonary isomerism. The stomach is located on either the left or the right and the spleen is small and has an abnormal shape. The apex of the heart pointed to the right or left. In addition malpositioning of heart outflow tracts is observed, the aorta is connected to the right ventricle and emerged from the heart in a ventral position and to the right of the pulmonary artery. This one is connected to either the left or the right ventricle. Belongs to the EGF-CFC (Cripto-1/FRL1/Cryptic) family.