Su, HanxiaSureda Gómez, MiquelRabaneda Lombarte, NeusGelabert, MariaXie, JianleiWu, WeiAdell i Creixell, Teresa2020-01-142020-01-142017-10-041553-7390https://hdl.handle.net/2445/147723β-Catenin, the core element of the Wnt/β-catenin pathway, is a multifunctional and evolutionarily conserved protein which performs essential roles in a variety of developmental and homeostatic processes. Despite its crucial roles, the mechanisms that control its context-specific functions in time and space remain largely unknown. The Wnt/β-catenin pathway has been extensively studied in planarians, flatworms with the ability to regenerate and remodel the whole body, providing a 'whole animal' developmental framework to approach this question. Here we identify a C-terminally truncated β-catenin (β-catenin4), generated by gene duplication, that is required for planarian photoreceptor cell specification. Our results indicate that the role of β-catenin4 is to modulate the activity of β-catenin1, the planarian β-catenin involved in Wnt signal transduction in the nucleus, mediated by the transcription factor TCF-2. This inhibitory form of β-catenin, expressed in specific cell types, would provide a novel mechanism to modulate nuclear β-catenin signaling levels. Genomic searches and in vitro analysis suggest that the existence of a C-terminally truncated form of β-catenin could be an evolutionarily conserved mechanism to achieve a fine-tuned regulation of Wnt/β-catenin signaling in specific cellular contexts.32 p.application/pdfengcc-by (c) Su, Hanxia et al., 2017http://creativecommons.org/licenses/by/3.0/esProteïnesCèl·lulesProteinsCellsinfo:eu-repo/semantics/article6737392020-01-14info:eu-repo/semantics/openAccess28976975