精制基因组决定因素,以逃避X染色体失活的基础
Samantha Peeters1, Tiffany Leung1,2, Oriol Fornes1,2
1Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
NAR genomics and bioinformatics
|June 1, 2023
概括
雌性哺乳动物通过X染色体失活 (XCI) 沉默一个X染色体. 研究人员确定了足够的基因促销元件来驱动从XCI逃脱,这对于理解基因表达差异和X无倍化症至关重要.
科学领域:
- 遗传学 遗传学 是一个
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 哺乳动物生物学 哺乳动物生物学
背景情况:
- 在雌性哺乳动物中,X染色体不活化 (XCI) 以表观遗传方式使一个X染色体沉默.
- 虽然大多数X链基因被静止,但很大一部分 (≥20%的人类) 逃脱了XCI,导致基于性别的基因表达差异和X无体现型.
- 管理XCI逃逸的监管机制在很大程度上是未知的.
研究的目的:
- 调查调节从X染色体失活 (XCI) 逃脱的机制.
- 确定涉及XCI逃逸基因表达的转录因子和调节元件.
主要方法:
- 在X染色体上对转录因子结合位进行了丰富分析.
- 利用转基因小鼠模型对小鼠X染色体上的转基因进行有针对性的整合和失活.
- 评估了RPS4X基因的促进子和基因元素,以确定它们驱动XCI逃逸的能力.
主要成果:
- 在XCI逃脱基因的转录开始部位确定了丰富的转录因子.
- 在已知的人类逃生基因RPS4X促进体中检测到顶部逃生丰富的转录因子.
- 一个小的转基因构造 (6 kb) 含有RPS4X促进体和基因元素,证明了从XCI.强大的逃脱.
- 确定基因邻近元素足以允许XCI逃脱.
结论:
- 基因近位元素足以驱动从X染色体失活 (XCI) 逃脱.
- 多个元素可以以特定的环境方式添加作用,以调节XCI逃逸.
- 研究结果提供了XCI逃逸的机制及其对X aneuploidies的潜在影响的见解.
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