New cell signaling pathways involved in Xenopus laevis neural crest development

MARCELA BONANO; TRISTÁN H. AGÜERO; JUAN P. FERNÁNDEZ; MANUEL J. AYBAR

Rosario, Santa Fé

Congreso; XLII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2006

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

The neural crest (NC) develops at the border between neural plate and the prospective epidermis in all vertebrate embryos. NC cells are highly migratory and generate many cell derivatives (neurons, pigment cells, cartilage, glial cells, etc). It has been demonstrated that the several signals (BMP4, Wnt, FGF, etc.) are involved in the induction of this tissue. However, the participation of other cell signals in NC specification has not been established. The analysis of expression patterns of the components of Banded hedgehog/Gli3 (Bhh/Gli3) and Endothelin1/Endothelin Receptor A (Edn1/Ednra) cell signaling pathways in Xenopus embryos revealed that both pathways are expressed in the NC territory. In order to study the role of Bhh/Gli3 and Edn1/Ednra pathways in the NC development we have carried out conditional gain- and loss-of function approaches. The microinjection of Bhh and Ednra mRNAs produced an increase in the expression of NC marker genes (FoxD3, Slug and Snail). On the other hand, the use of specific inhibitors of these signals, the microinjection of dominant negative constructs and morpholino antisense oligonucleotides against Bhh/Gli3 and Ednra caused a decrease in the expression of NC markers. Our results suggest that Bhh/Gli3 and Edn1/Ednra signaling pathways are required for the initial induction, maintenance of specification and migration of NC cells in Xenopus embryos.