-実験動物開発室-

 The internal organs of vertebrates show left-right (L-R) asymmetry in their anatomy and physiology. L-R patterning is determined early during development. Lefty and Nodal have been found to be expressed asymmetrically in developing mouse embryo. Both of these proteins are expressed in the lateral plate mesoderm exclusively on the left side; Nodal acts as the left-side determinant, whereas Lefty functions as a feedback inhibitor of Nodal. Lefty1-deficient and Nodal-deficient mice showed a variety of L-R positional defects in visceral organs including left and right isomerism, respectively.