The Wnt/β-catenin signalling pathway is a key pathway involved in a myriad of developmental processes, from body axis patterning to cell migration and fate specification. The role of the Wnt pathway is to regulate transcription of specific target genes, and it has long been thought that the driving event for this is the recruitment of β-catenin to specific gene loci on the chromatin. Now, however, on p. , Stefan Hoppler and colleagues provide in vivo evidence that, rather than β-catenin recruitment, it is instead the context-specific events that occur subsequent to β-catenin binding that enable gene-specific regulation. The authors use ChIP-seq to show that β-catenin is recruited to many genomic loci in Xenopus early embryonic development, while RNA-seq reveals that many of these β-catenin-bound loci are not transcriptionally regulated by Wnt signalling in this context. Instead, the transcriptional response depends on the presence or absence of additional mechanisms, for example FGF and BMP signalling. This important study advances the current understanding and interpretation of how Wnt/β-catenin signalling operates to regulate gene-specific transcription in different developmental contexts.
