Coordinated Tcf7l2 regulation in a mouse model implicates Wnt signaling in fetal alcohol spectrum disorders

Abstract

Mouse models of fetal alcohol spectrum disorders (FASD) have repeatedly identified genes with long-term changes in expression, DNA methylation, noncoding RNA, and histone modifications in response to neurodevelopmental alcohol exposure. Articulation of FASD is achieved via alcohol’s effect on gene expression, likely involving epigenetic regulation. The list of genes affected is large and heterogeneous, depending on experimental protocol. We present reanalysis and synthesis of results highlighting the Wnt transcription factor 7 like 2 (Tcf7l2) gene as uniquely compatible with hippocampal DNA methylation, histone modifications, and gene expression changes in a coordinated response to neurodevelopmental alcohol exposure. We data-mined the literature for Tcf7l2 alterations in response to prenatal alcohol exposure. Four studies identified changes in brain Tcf7l2 expression in different FASD models. Further, we performed an in silico TCF7L2 binding site analysis for FASD mouse model data sets. Seven of these published gene lists were significantly enriched for TCF7L2 binding, indicating potential functional relationships. Finally, TCF7L2 is involved in regulation of hundreds of genes, with a role in brain development, myelination, and neuronal function. Tcf7l2 may be involved in neurological defects associated with alcohol exposure via dysregulation of many genes through Wnt signaling. Further functional work is warranted to validate this model for FASD.