精确编辑的基因组尾巴扰乱了试管体中多基因基因表达控制的多基因表达控制
Markéta Novotná1, Michele Tinti1, Joana R C Faria2
1School of Life Sciences, University of Dundee, Dundee, UK.
Nature communications
|July 4, 2025
概括
希斯H4尾部的修饰调节了Trypanosoma brucei中的基因表达. 模仿 lysine 4 或 14 的乙化特征的特定突变减少了邻近基因的表达,显示出对多基斯特朗转录的直接控制.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 寄生虫学的寄生虫学
背景情况:
- 像Trypanosoma brucei这样的试类动物的转录主要是多基斯特的,涉及RNA聚合酶II.
- 在T. brucei中,RNA聚合酶II促进体的特征是染色质富含基因素,其N端尾部表现出特定的翻译后修饰.
研究的目的:
- 为了研究基因组 H4 N-终端尾部残留物在控制 T. brucei. 的基因表达中的作用.
- 为了设计T. brucei菌株,表达专门的突变组织蛋白,以研究基因表达调节.
主要方法:
- 利用一种可诱导的CRISPR-Cas9系统来删除内源性组织素H4基因,并补充单个异胎性H4基因.
- 在六个基因组H4 N端尾氨酸残留物上进行和突变,产生384种不同的突变.
- 进行全基因组测序,转录组分析和蛋白质组分析以表征突变菌株.
主要成果:
- 通过测序和转录组分析验证的专门表达突变基因组的工程"基因组H4"菌株.
- 鉴定了19种表达明显的H4 lysine 4或lysine 14突变的可活性突变菌株;H4 lysine 10突变是致命的.
- H4氨酸4谷氨酸突变体显示,RNA聚合酶II促进体附近的基因表达显著减少,模仿升高的乙化.
结论:
- 通过修改的组分离子H4 N-终端尾部残留物对多基斯特龙表达控制的直接证据.
- 特定的基因素修饰,特别是在H4 lysine 4中,在T. brucei.中调节基因表达方面发挥着至关重要的作用.
- 这些发现提供了对寄生虫原生动物中非传统的基因调节机制的洞察.
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