Wnt/β-catenin signalling is required for pole-specific chromatin remodeling during planarian regeneration

Abstract

For successful regeneration, the identity of the missing tissue must be specified according to the pre-existing tissue. Planarians are ideal for the study of the mechanisms underlying this process; the same field of cells can regrow a head or a tail according to the missing body part. After amputation, the differential activation of the Wnt/β-catenin signal specifies anterior versus posterior identity. Initially, both wnt1 and notum (Wnt inhibitor) are expressed in all wounds, but 48 hours later they are restricted to posterior or anterior facing wounds, respectively, by an unknown mechanism. Here we show that 12 hours after amputation, the chromatin accessibility of cells in the wound region changes according to the polarity of the pre-existing tissue in a Wnt/β-catenin-dependent manner. Genomic analyses suggest that homeobox transcription factors and chromatin-remodeling proteins are direct Wnt/β-catenin targets, which trigger the expression of posterior effectors. Finally, we identify FoxG as a wnt1 up-stream regulator, probably via binding to its first intron enhancer region.

Objective scanning-based fluorescence cross-correlation spectroscopy (Scan-FCCS) for studying the fusion dynamics of protein phase separation

“…It prevents β-catenin degradation by inhibiting its phosphorylation, leading to β-catenin accumulation and nuclear translocation, which can activate certain genes related to cancer progression. [35][36][37][38][39] Moreover, CRDBP binds to β-catenin, potentially stabilizing β-catenin, and is implicated in β-catenin's cellular functions. Our studies suggest CRDBP's role in β-catenin recruitment.…”

LIM-HD transcription factors are required for regeneration of neuronal and intestinal cell subtypes in planarians

“…Transcription factors (TFs) play key roles in multiple aspects of animal development. In planarians, many conserved TFs have been identified (Suzuki-Horiuchi et al, 2021) and characterized to be required for the regeneration of multiple cells, tissues and organs including the intestine (Flores et al, 2016; Forsthoefel et al, 2012; Forsthoefel et al, 2020; González-Sastre et al, 2017), the eyes (Lapan and Reddien, 2011; Lapan and Reddien, 2012; Mannini et al, 2004; Pineda et al, 2000), the central nervous system (Brown et al, 2018; Coronel-Córdoba et al, 2022; Cowles et al, 2013; Cowles et al, 2014; Currie and Pearson, 2013; Fraguas et al, 2014; März et al, 2013; Roberts-Galbraith et al, 2016; Ross et al, 2018), the epidermis (Dubey et al, 2022; Tu et al, 2015), the pharynx (Adler et al, 2014), the pigment cells (He et al, 2017; Wang et al, 2016), the musculature (Scimone et al, 2017; Scimone et al, 2018), the excretory system (Scimone et al, 2011), as well as for the establishment of axial polarity (Blassberg et al, 2013; Chen et al, 2013; Felix and Aboobaker, 2010; Hayashi et al, 2011; Pascual-Carreras et al, 2023; Scimone et al, 2014; Tian et al, 2021; Vásquez-Doorman and Petersen, 2014).…”

LIM-HD transcription factors control axial patterning and specify distinct neuronal and intestinal cell identities in planarians

“…Transcription factors (TFs) play key roles in multiple aspects of animal development. In planarians, many conserved TFs have been identified [11] and characterized to be required for the regeneration of multiple cells, tissues and organs including the intestine [12][13][14][15], the eyes [16][17][18][19], the central nervous system [20][21][22][23][24][25][26][27][28], the epidermis [29,30], the pharynx [31], the pigment cells [32,33], the musculature [34,35], the excretory system [36], as well as for establishing axial polarity [37][38][39][40][41][42][43][44].…”