... signaling at the node is responsible for the L-R reversal of visceral organs in the inv mutant mouse. In the node of wild-type embryos, the expression of Nodal and Cerl2 ( Dand5 ), which encodes an inhibitor of Nodal, is asymmetric, with the level of Nodal expression being higher on the left side...

...Daisuke Watanabe; Yukio Saijoh; Shigenori Nonaka; Genta Sasaki; Yayoi Ikawa; Takahiko Yokoyama; Hiroshi Hamada Inversin (Inv), a protein that contains ankyrin repeats, plays a key role in left-right determination during mammalian embryonic development, but its precise function remains unknown...