FIGURE 1.

Schematic drawing showing the mechanisms through which CHD7 controls gene expression. (A) CHD7 is predominantly recruited at active enhancers (H3K4me1 mark, red dots) and, even if with less extent, promoters (H3K4Me3 mark, green dots) by the presence of pioneer transcription factors and specific histone methylations. The CHD7-induced chromatin opening via nucleosome remodeling allows regulatory elements to become more accessible to additional transcription factors (TFs) at both enhancers (I) and promoters (II). Furthermore, co-activators, such as histone acetylases, may be recruited as well at enhancer sites (I), thus promoting further histone modifications (H3K27ac, yellow dots) associated with enhanced transcription activity. (B) CHD7 can also act as transcription repressor. Chromatin remodeling might result in TFs complexed with co-repressors that promote repressive histone modification (H3K27me3, black dot) (I). Conversely, CHD7 might promote nucleosome repositioning, resulting in less accessible chromatin and in decreased transcriptional activity (II).