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bioRxiv · 10.1101/2022.10.15.512282

β-catenin-dependent endomesoderm specification appears to be a Bilateria-specific co-option

Lebedeva, T.·Bostroem, J.·Moersdorf, D.·Niedermoser, I.·Genikhovich, E.·Adameyko, I.·Genikhovich, G.
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Abstract

Endomesoderm specification based on a maternal {beta}-catenin signal and axial patterning by interpreting a gradient of zygotic Wnt/{beta}-catenin signalling was suggested to predate the split between Bilateria and their evolutionary sister Cnidaria. However, in Cnidaria, the roles of {beta}-catenin signalling in both these processes have not been proven directly. Here, by tagging the endogenous {beta}-catenin protein in the sea anemone Nematostella vectensis, we show that the oral-aboral axis in a cnidarian is indeed patterned by a gradient of {beta}-catenin signalling. Unexpectedly, in a striking contrast to Bilateria, Nematostella endoderm specification takes place opposite to the part of the embryo, where {beta}-catenin is translocated into the nuclei. This suggests that {beta}-catenin-dependent endomesoderm specification is a Bilateria-specific co-option, which may have linked endomesoderm specification with the subsequent posterior-anterior patterning.

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Lebedeva, T., Bostroem, J., Moersdorf, D., Niedermoser, I., Genikhovich, E., Adameyko, I., Genikhovich, G.. 2022-10-16. β-catenin-dependent endomesoderm specification appears to be a Bilateria-specific co-option. https://doi.org/10.1101/2022.10.15.512282

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