Anteroposterior polarity and elongation in the absence of extra-embryonic tissues and of spatially localised signalling in gastruloids: mammalian embryonic organoids.

ABSTRACT: The establishment of the anteroposterior (AP) axis is a crucial step during animal embryo development. In mammals, genetic studies have shown that this process relies on signals spatiotemporally deployed in the extra-embryonic tissues that locate the position of the head and the onset of gastrulation, marked by T/Brachyury (T/Bra) at the posterior of the embryo. Here, we use gastruloids, mESC-based organoids, as a model system with which to study this process. We find that gastruloids localise T/Bra expression to one end and undergo elongation similar to the posterior region of the embryo, suggesting that they develop an AP axis. This process relies on precisely timed interactions between Wnt/β-catenin and Nodal signalling, whereas BMP signalling is dispensable. Additionally,

SUBMITTER: Turner DA 

PROVIDER: S-EPMC5702072 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature