Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
Heart Center, University Hospital Cologne, Cologne, Germany.
Nat Commun. 2021 May 21;12(1):3014. doi: 10.1038/s41467-021-23327-1.
Members of the chromodomain-helicase-DNA binding (CHD) protein family are chromatin remodelers implicated in human pathologies, with CHD6 being one of its least studied members. We discovered a de novo CHD6 missense mutation in a patient clinically presenting the rare Hallermann-Streiff syndrome (HSS). We used genome editing to generate isogenic iPSC lines and model HSS in relevant cell types. By combining genomics with functional in vivo and in vitro assays, we show that CHD6 binds a cohort of autophagy and stress response genes across cell types. The HSS mutation affects CHD6 protein folding and impairs its ability to recruit co-remodelers in response to DNA damage or autophagy stimulation. This leads to accumulation of DNA damage burden and senescence-like phenotypes. We therefore uncovered a molecular mechanism explaining HSS onset via chromatin control of autophagic flux and genotoxic stress surveillance.
染色质螺旋酶-DNA 结合(CHD)蛋白家族的成员是与人类病理学相关的染色质重塑因子,其中 CHD6 是研究最少的成员之一。我们在一位临床上表现出罕见的 Hallermann-Streiff 综合征(HSS)的患者中发现了一个 CHD6 无义突变的从头突变。我们使用基因组编辑生成了同源的 iPSC 系,并在相关细胞类型中模拟 HSS。通过将基因组学与体内和体外功能测定相结合,我们表明 CHD6 在多种细胞类型中结合了一批自噬和应激反应基因。HSS 突变影响 CHD6 蛋白的折叠,削弱了其在 DNA 损伤或自噬刺激时招募共重塑因子的能力。这导致 DNA 损伤负担的积累和衰老样表型。因此,我们揭示了一种分子机制,通过染色质对自噬通量和遗传毒性应激监测的控制来解释 HSS 的发生。