Retinoic acid signaling organizes endodermal organ specification along the entire antero-posterior axis.

ABSTRACT:

Background

Endoderm organ primordia become specified between gastrulation and gut tube folding in Amniotes. Although the requirement for RA signaling for the development of a few individual endoderm organs has been established a systematic assessment of its activity along the entire antero-posterior axis has not been performed in this germ layer.

Methodology/principal findings

RA is synthesized from gastrulation to somitogenesis in the mesoderm that is close to the developing gut tube. In the branchial arch region specific levels of RA signaling control organ boundaries. The most anterior endoderm forming the thyroid gland is specified in the absence of RA signaling. Increasing RA in anterior branchial arches results in thyroid primordium repression and the induction of more

SUBMITTER: Bayha E 

PROVIDER: S-EPMC2690404 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature