Characterization of sclerotomal genes during Xenopus laevis embryogenesis

SÁNCHEZ R. S.; MÓNACO M. E.; SÁNCHEZ S. S.

Puerto madryn, Chubut

Congreso; XLVI Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology (SAIB); 2010

SAIB

The axial skeleton develops from the sclerotome, a cell mass derived from the somites, segmentally repeated units located on either side of the neural tube. Those cells take up positions around the notochord and neural tube, when they leave the somites, for later differentiation to cartilage and bone. The anurans are characterized for having a highly specialized vertebral column with a reduced number of vertebral elements. The amphibian sclerotomal cells have not been studied and knowledge of the molecular programs leading to morphogenesis of vertebral elements is relevant taking account the broad range of dysmorphic syndromes affecting axial skeleton formation. In this work we characterize the expression pattern of the genes Xpax1, Xpax9 and Xuncx by in situ hybridization and RT-PCR. We found that these transcription factors are expressed in the sclerotomal cells as well as in the pharyngeal arches from tail bud stage, which is consistent with other vertebrate. Comparison of the derived protein sequences of these genes with their orthologs reveals a striking conservation of their DNA-binding domain which has been maintained throughout of vertebrate evolution. We also carried out experiments of gain of function by microinjection of the mRNAs of these genes showing their potential role in the Xenopus laevis development.