与初级宪法MLH1表皮相结合的改变色素景观和3D相互作用
Paula Climent-Cantó1,2, Marc Subirana-Granés3, Mireia Ramos-Rodríguez3
1Hereditary Cancer Group, ONCOBELL Program, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Spain.
Clinical epigenetics
|December 31, 2024
概括
宪法MLH1表位 (CME) 涉及改变的MLH1促进体调节. 初级CME表现出明显的3D染色体相互作用和潜在的遗传变化,为其分子机制提供了洞察力.
科学领域:
- 遗传学和表观遗传学
- 癌症倾向症候群 癌症倾向症候群
- 分子生物学分子生物学
背景情况:
- 林奇综合征 (LS) 增加了癌症的风险,通常是由于不匹配的修复基因变异.
- 宪法MLH1表皮化 (CME) 是较少见的LS病因,涉及MLH1促进物甲基化.
- 初级CME是de novo产生的,并且可以在几代人之间传承,其潜在机制尚不清楚.
研究的目的:
- 调查原发性CME中的遗传和基因调节性改变.
- 阐明原始CME的起源和维持背后的分子机制.
主要方法:
- 利用链接读取全基因组测序 (WGS) 来识别CME载体中的遗传变化.
- 使用RNA测序 (RNA-seq),ATAC-seq,H3K27ac CUT&Tag和UMI-4C来分析基因表达,染色体可访问性和3D染色体相互作用.
- 使用一种特定的MLH1促进子SNP (rs1800734) 作为报告者来评估异位基因特定的染色质构成.
主要成果:
- 与非甲基化等位基相比,epimutant MLH1等位基表现出封闭的染色体构造和降低的H3K27ac水平.
- 证明了表突性MLH1促进体中的差异性3D染色质接触,包括与远程调节元件的改变相互作用.
- 在CME载体的促进体接触区域中发现了罕见的遗传变异,可能会影响转录因子的结合.
结论:
- 主要的CME在与邻近的基因和调节元素的相互作用中表现出异位基因特异性的差异.
- 确定的cis-regulatory区域可能在CME的起源和维持中发挥作用.
- 需要进一步的研究,才能充分理解原发性CME背后的分子机制.
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