... pathway was significantly reduced in Sp 2H /Sp 2H embryos. To resolve current controversy over the cell autonomy of the splotch cardiac neural crest defect, we performed reciprocal grafts of premigratory neural crest between wild type and splotch embryos. Sp 2H /Sp 2H cells migrated normally...

... of cranial neural crest migrate from the hindbrain into the outflow tract of the heart where they contribute to the septum that divides the pulmonary and aortic channels. In Splotch mutant mice, which lack a functional Pax3 gene, migration of cardiac neural crest is deficient and aorticopulmonary septation...

..., by organ culture in vitro, with consequent lack of up-regulation of Pax3 . Occipital neural crest cell outgrowths in vitro were also shown to express Pax3 . Mutation of Pax3 , as occurs in the splotch (Sp 2H ) mouse, results in development of conotruncal heart defects including persistent truncus...

... plate. Met expression in the lateral dermomyotome and limb bud coincides with expression of Pax-3 , a marker for migrating muscle precursor cells in the somite and limb. Splotch-2H and Splotch-delayed mice, which harbor mutations in Pax-3 , show major disruptions in early limb muscle development...

... tendons muscle homeobox embryogenesis murine limb splotch The development of the vertebrate limb is a popular system for studying the mechanisms controlling patterning and morpho-genesis. These studies have focussed on formation of the skeletal limb elements and, more recently, muscle...

... in the developing limbs express Pax-3 . Significantly, in homozygous splotch mutant mice, which synthesize altered Pax-3 mRNA but make no normal protein, no cells positive for Pax-3 transcripts can be detected in the region of migrating limb muscle precursors or in the limb itself. In contrast, myotomal precursor...