Pitx2, a Bicoid-Type Homeobox V Gene, Is Involved in a Lefty-Signaling Pathway in Determination of Left-Right Asymmetry

• Published in: Cell 1998-08, Vol.94 (3), p.299-305
• Main Authors: Yoshioka, H, Meno, C, Koshiba, K, Sugihara, M, Itoh, H, Ishimaru, Y, Inoue, T, Ohuchi, H, Semina, E V, Murray, J C, Hamada, H, Noji, S
• Format: Article
• Language: English
• ISSN: 0092-8674

Signaling molecules such as Activin, Sonic hedgehog, Nodal, Lefty, and Vg1 have been found to be involved in determination of left-right (L-R) asymmetry in the chick, mouse, or frog. However, a common signaling pathway has not yet been identified in vertebrates. We report that Pitx2, a bicoid-type homeobox gene expressed asymmetrically in the left lateral plate mesoderm, may be involved in determination of L-R asymmetry in both mouse and chick. Since Pitx2 appears to be downstream of lefty-1 in the mouse pathway, we examined whether mouse Lefty proteins could affect the expression of Pitx2 in the chick. Our results indicate that a common pathway from lefty-1 to Pitx2 likely exists for determination of L-R asymmetry in vertebrates.