... limb mesenchyme results in polydactyly and in brachydactyly and a failure of subperisoteal bone formation, defects that are attributable to abnormal sonic hedgehog and Indian hedgehog signalling, respectively. Like talpid 3 chicken limbs, the mutant mouse limbs are syndactylous with uneven digit...

... replace FGF8 in limb skeletal development. We also show that the increase in FGF signaling that occurs when the Fgf4 gain-of-function allele is activated in a wild-type limb bud causes formation of a supernumerary posterior digit (postaxial polydactyly), as well as cutaneous syndactyly between all...

... demonstrated interaction between Dkk1 and the Wnt coreceptors Lrp5 and Lrp6 by analysis of several types of double mutants. The polydactyly of Dkk1 d/d mice was corrected by reduced expression of Lrp5 or Lrp6 . The posterior digit loss and axial truncation characteristic of Lrp6 null mice was partially...

... for the three Gli genes in mice, we have produced a Gli1 mutant and analyzed the phenotypes of Gli1/Gli2 and Gli1/3 double mutants. Gli3 xt mutants have polydactyly and dorsal CNS defects associated with ectopic Shh expression, indicating GLI3 plays a role in repressing Shh . In contrast, Gli2 mutants have five...

..., mutation of Cart1 exacerbates Alx4- dependent polydactyly in a manner that is dependent on gene dosage. Second, there are complex genetic interactions in the craniofacial region that reveal a role for both genes in the fusion of the nasal cartilages and proper patterning of the mandible, as well as other...

... been shown to be able to mediate the function of the ZPA. Several naturally occurring mouse mutations with the phenotype of preaxial polydactyly exhibit ectopic Shh expression at the anterior limb margin. In this study, we report the molecular characterization of a spontaneous mouse mutation...

... polydactyly. The polydactyly is associated with the formation of an ectopic anterior ZPA, as indicated by anterior expression of Sonic hedgehog, HoxD13 and fibroblast growth factor-4 . The expression of other candidate regulators of anterior-posterior positional information in the limb bud, including HoxB8...

... genes transgenic mice neural tube floor plate notochord holoprosencephaly polydactyly mouse During the development of the nervous system, the relative position of the neural precursors along the rostrocaudal and dorsoventral axis is a major determinant of their final differentiation fate...

... in order to gain an insight into function of this protein. The results of this study indicate that CRABP-II is involved in the patterning of the forelimb, as loss of this protein causes postaxial polydactyly. It is surprising, given the widespread expression of the CRABP-II gene throughout development...