1: Dev Biol. 2001 Nov 15;239(2):270-80. 

Hypaxial muscle migration during primary myogenesis in Xenopus laevis.

Martin BL, Harland RM.

Department of Molecular and Cell Biology, University of California, Berkeley,
California 94720-3202, USA.

In contrast to many vertebrates, the ventral body wall muscles and limb muscles
of Xenopus develop at different times. The ventral body wall forms in the
tadpole, while limb (appendicular) muscles form during metamorphosis to the
adult frog. In organisms that have been examined thus far, a conserved mechanism
has been shown to control migratory muscle precursor specification, migration,
and differentiation. Here, we show that the process of ventral body wall
formation in Xenopus laevis is similar to hypaxial muscle development in
chickens and mice. Cells specified for the migratory lineage display an
upregulation of pax3 in the ventro-lateral region of the somite. These
pax3-positive cells migrate ventrally, away from the somite, and undergo
terminal differentiation with the expression of myf-5, followed by myoD. Several
other genes are selectively expressed in the migrating muscle precursor
population, including neural cell adhesion molecule (NCAM), Xenopus kit related
kinase (Xkrk1), and Xenopus SRY box 5 (sox5). We have also found that muscle
precursor migration is highly coordinated with the migration of neural
crest-derived melanophores. However, by extirpating neural crest at an early
stage and allowing embryos to develop, we determined that muscle precursor
migration is not dependent on physical or genetic interaction with melanophores.
Copyright 2001 Academic Press.

PMID: 11784034 [PubMed - indexed for MEDLINE]


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