Opposing Nodal/Vg1 and BMP signals mediate axial patterning in embryos of the basal chordate amphioxus.

ABSTRACT: The basal chordate amphioxus resembles vertebrates in having a dorsal, hollow nerve cord, a notochord and somites. However, it lacks extensive gene duplications, and its embryos are small and gastrulate by simple invagination. Here we demonstrate that Nodal/Vg1 signaling acts from early cleavage through the gastrula stage to specify and maintain dorsal/anterior development while, starting at the early gastrula stage, BMP signaling promotes ventral/posterior identity. Knockdown and gain-of-function experiments show that these pathways act in opposition to one another. Signaling by these pathways is modulated by dorsally and/or anteriorly expressed genes including Chordin, Cerberus, and Blimp1. Overexpression and/or reporter assays in Xenopus demonstrate that the functions of these proteins

SUBMITTER: Onai T 

PROVIDER: S-EPMC4781670 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature