Impaired CHD6 function links misregulation of autophagy and DNA damage response to premature ageing [ChIP-Seq]

Members of the Chromodomain-Helicase-DNA binding (CHD) protein family are chromatin remodelers critically implicated in human pathologies. CHD6 is the least studied member of this family, and we were motivated to dissect its in-cell roles by discovering a mutated CHD6 allele in a patient suffering from the rare Hallermann-Streiff premature aging syndrome (HSS). We generated isogenic iPSC lines carrying (or not) this single point mutation in the CHD6 SANT/SLIDE domain, which allow studying HSS-relevant cell identities. Using these lines, we show for the first time that CHD6 binds the promoters of a cohort of autophagy and stress response genes across cell types. This CHD6 mutation impairs its ability to recruit co-factors and regulate genes in response to DNA damage and autophagy stimulation, thus leading to accumulation of unresolved DNA damage burden. By combining genomics and functional assays, we describe a molecular mechanism underlying chromatin control of autophagic flux and genotoxic stress surveillance that is broadly applicable to human cell types and can explain HSS establishment.