Year: 2019
Type: preprint
Abstract: The ß-catenin protein has two major known functions in animal cells. It keeps epithelial tissue homeostasis by its connection with Adherens Junctions (AJ), and it serves as a transcriptional cofactor along with Lef/Tcf to enter the nucleus and regulate target genes of the Wnt/ß-catenin (cWnt) signaling pathway. To assess the ancestral role of ß-catenin during development we examined its distribution and function in the ctenophore Mnemiopsis leidyi (one of the earliest branching animal phyla) by using ctenophore-specific antibodies and mRNA injection. We found that ß-catenin protein never localizes to cell-cell contacts during embryogenesis as it does in other metazoans, most likely because ctenophore-cadherins do not have the cytoplasmic domain required for interaction with the catenin proteins. Downregulation of zygotic Ml ß-catenin signaling led to the loss of endodermal and mesodermal tissues indicating that nuclear ß-catenin may have a deep role in germ-layer evolution. Our results indicate that the ancestral role for ß-catenin was in the cell-fate specification and not in cell adhesion and also further emphasizes the critical role of this protein in the evolution of tissue layers in metazoans.
DOI: 10.1101/520957
Institutions: University of Florida, University of Miami
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2909729154