Novel role of Notch1 in early dorsal-ventral axis development

CASTRO COLABIANCHI, AITANA M.; BAEZ, MARÍA VERÓNICA; KODJABACHIAN, LAURENT; REVINSKI, DIEGO R.; MONTI, RENATO JOSÉ; FRANCHINI, LUCÍA F.; ENCINAS, PAULA INÉS; RODRÍGUEZ ABINAL, MATEO; LÓPEZ, SILVIA L.

Boston

Congreso; Society for Developmental Biology 78th Annual Meeting; 2019

Society for Developmental Biology

Program Abstract #348Novel role of Notch1 in early dorsal-ventral axis development Aitana Castro Colabianchi1, Diego R. Revinski2, Paula I. Encinas1, María Verónica Baez1, Renato J. Monti1, Mateo Rodríguez Abinal1, Laurent Kodjabachian2 , Lucía F. Franchini1, Silvia L. López1 1CONICET, AR; 2CNRS, FRWe have previously demonstrated that early ventral Notch1 activity restricts dorsoanterior developmentin Xenopus, abolishing the dorsalizing activity of β-catenin by reducing its steady state levels. In the present work,we demonstrate by western blot, quantitative image analysis, in situ hybridization and qRT-PCR, that Notch1mRNA and protein are enriched in the ventral region from the beginning (one cell stage) of embryogenesis inXenopus. Knockdown experiments indicate that Notch1 is necessary for the normal expression of genes essential for ventral-posterior development. This is the earliest sign of ventral development, preceding the localized expression of wnt8a, bmp4 and Ventx genes in the ventral center and the dorsal accumulation of nuclear β-catenin. These results indicate that during early embryogenesis ventrally located Notch1 promotes the development of the ventral center. Together with our previous evidence, these results suggest that ventralenrichment of Notch1 underlies the process by which Notch1 participates in restricting nuclear accumulation of β- catenin to the dorsal side by a dual mecanism, reducing β-catenin levels and favouring ventral centers genes.Funding: Agencia Nacional de Promoción Científica y Tecnológica, Argentina (PICT 2011-1559 and PICT 2014-2020to S.L.L.; PICT 2015-1726 and PICT 2016-1429 to L.F.F.; the Consejo Nacional de Investigaciones Científicas yTécnicas, Argentina (PIP 2012-0508 and PIP 2015-0577 Centre National de la Recherche Scientifique and AixMarseilleUniversité, and a research grant from the Fondation pour la Recherche Médicale (DEQ20141231765 toL.K.)