艾滋病毒-1利用LEDGF在转录中的作用来定位整合
bioRxiv : the preprint server for biology
|July 15, 2024
概括
透镜上皮衍生的生长因子 (LEDGF) 将RNA聚合酶II招募到活性促进体,促进HIV-1跨基因的整合. LEDGF的双重作用解释了其参与MLL1驱动型白血病的原因.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 艾滋病毒-1整合向通过整合酶和宿主因子LEDGF积极转录的基因.
- 已知LEDGF作为协同激活剂和基因素伴侣的作用与其基因整合功能相冲突.
研究的目的:
- 阐明LEDGF在HIV-1整合中的精确作用及其与染色质的相互作用.
- 调查LEDGF的招聘机制及其对基因特异性整合的贡献.
主要方法:
- 全基因组染色体映射以识别LEDGF,H3K4me3和RNA聚合酶II丰富物.
- 分析LEDGF与MLL1的相互作用及其对RNA Pol II招募的影响.
- 评估H3K36me3在LEDGF介导的集成特异性中的作用.
主要成果:
- 在活跃促进体的转录起点 (TSS) 上,LEDGF被丰富,与H3K4me3和RNA Pol II.相关联.
- MLL1在招募LEDGF到促进者的过程中发挥着关键作用,LEDGF反过来招募RNA Pol II.
- 在TSS的LEDGF丰富与跨基因体的整合水平有很强的相关性,独立于H3K36me3.3.
结论:
- LEDGF的功能是双重的:由MLL1招募到促进器,以招募RNA Pol II,然后穿越基因以促进HIV-1的整合.
- 这种机制为LEDGF在MLL1驱动的婴儿急性白血病和成人急性髓性白血病中的作用提供了洞察力.
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