CONICET | Buscador de Institutos y Recursos Humanos

Vertebrates axes are maternally biasedAitana Manuela Castro Colabianchi 1 , Marcelo Rubinstein 2 , Silvia L. López 1 1 Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas yTécnicas, Instituto de Biología Celular y Neurociencias ?Prof. E. De Robertis? (IBCN),Facultad de Medicina, Laboratorio de Embriología Molecular ?Prof. Dr. Andrés E.Carrasco?, Buenos Aires, Argentina. 2 INGEBI-CONICET y FCEyN, UBA. It is considered that the radial symmetry around the polarized Animal-Vegetal axis ofthe Xenopus egg is broken after fertilization by relocation of dorsal determinants. Thisresults in local stabilization of maternal β-catenin and the induction of the dorsalsignaling centers that lead to the establishment of the Spemann-Mangold?s Organizer(Gerhart et al., 1989) (Gilbert, 2014). It is generally accepted that the signalingpathways activation that defines the Anterior-Posterior, Dorsal-Ventral and Left-Rightaxes in vertebrates takes place during zygotic transcription, and that the differentialactivation of genes in different groups of cells defines pluripotent embryonic cellpopulations with different prospective fates, thus establishing the embryonic body axes.Here we show the first results in vertebrate models that indicate that moleculespreviously shown to be involved in patterning the embryonic body axes or in decisionsin the embryonic/ab-embryonic axes like Notch1 (Rayon et al., 2014) (CastroColabianchi et al., 2018) are asymmetrically distributed in the unfertilized egg. Wethink that this primary asymmetry might lead to the asymmetric inheritance of cellularcomponents of the unfertilized egg by the early embryo, and perhaps, they would havesome participation in differential signaling in the derived embryonic cell populations.