Identification and characterization of a novel gene, Halfback, required for somite formation and anterior-posterior patterning.

摘要

The classical mouse mutation tail kinks disrupts the normal formation and patterning of cervical and tail vertebrae. Using a positional cloning approach, we have identified a novel gene, Halfback, which is disrupted by insertion of an intracisternal-A particle element in tail kinks mutant mice. Halfback is expressed in a dynamic stripe-like pattern specifically in the rostral presomitic mesoderm, and becomes localized to the posterior half of prospective somites. Targeted inactivation of Halfback resulted in a stronger allele than the tail kinks allele and demonstrated that Halfback is necessary for the formation of axial structures that are normally derived from the posterior halves of somites. HALFBACK interacts with Groucho/TLE co-repressor proteins through a conserved WRPW motif, and represents a new component of the Notch-Delta-Mesp regulatory loop that controls anterior-posterior patterning of prospective somites.