Expression patterns of signalling molecules and transcription factors in the early rabbit embryo and their significance for modelling amniote axis formation

• DOI: 10.1007/s00427-021-00677-w
• Publication Date: 2021-06-07T17:03:31Z
• Authors: Ruben Plöger; Christoph Viebahn
• Keywords: Amniote; Epiblast; Primitive streak; Body plan; Developmental Biology

Abstract The anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic activities. In chick, experimentally proven activity signalling molecules and transcription factors lead to concept ‘global positioning system’ for initial formation whereas in (mammotypical) rabbit embryo, series morphological or molecular are part putative ‘three-anchor-point model’. Because circular expression patterns genes involved exist both groups prior to, during, gastrulation may thus be suited reconcile these models, selected known namely ones coding eomes tbx6, molecule wnt3 wnt inhibitor pkdcc, were analysed embryonic disc using situ hybridisation placing emphasis on their germ layer location. Peripheral all layers found initially complementary pkdcc hypoblast early formation. Pkdcc then appears — together posterior-anterior gradient epiblast posteriorly before emerging primitive streak marked by tbx6 at its anterior posterior extremities, respectively. Conserved deduced from some this data point shared mechanisms while reshaping localised gene discussed as model’ establishing mammalian plan.