A novel gain-of-function mutation of the proneural IRX1 and IRX2 genes disrupts axis elongation in the Araucana rumpless chicken.

ABSTRACT: Axis elongation of the vertebrate embryo involves the generation of cell lineages from posterior progenitor populations. We investigated the molecular mechanism governing axis elongation in vertebrates using the Araucana rumpless chicken. Araucana embryos exhibit a defect in axis elongation, failing to form the terminal somites and concomitant free caudal vertebrae, pygostyle, and associated tissues of the tail. Through whole genome sequencing of six Araucana we have identified a critical 130 kb region, containing two candidate causative SNPs. Both SNPs are proximal to the IRX1 and IRX2 genes, which are required for neural specification. We show that IRX1 and IRX2 are both misexpressed within the bipotential chordoneural hinge progenitor population of Araucana embryos. Expression analysis

SUBMITTER: Freese NH 

PROVIDER: S-EPMC4221472 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature