全基因组表观遗传标记和转录控制的动态转换确定了T细胞的身份
Jingli A Zhang1, Ali Mortazavi, Brian A Williams
1Division of Biology 156-29, California Institute of Technology, Pasadena, CA 91125, USA.
Cell
|April 17, 2012
概括
这项研究揭示了转录因子GATA-3和PU.1如何通过调节基因表达和表观遗传标记来控制T细胞发育. 它揭示了T细胞承诺期间基因激活和抑制的动态机制.
科学领域:
- 免疫学 免疫学 免疫学
- 发育生物学 发展生物学
- 分子生物学分子生物学
背景情况:
- 细胞的发育是一个复杂的过程,涉及到多能前体的参与.
- 像GATA-3和PU.1这样的转录因子在指导T细胞分化中起着至关重要的作用.
- 了解控制这些转变的分子机制对于理解免疫系统发育至关重要.
研究的目的:
- 阐明控制T细胞结合的分子机制.
- 研究T细胞发育过程中的全基因组转录和表观遗传变化.
- 确定GATA-3和PU.1在调节基因表达和沉默替代血统基因中的作用.
主要方法:
- 利用RNA测序 (RNA-seq) 来分析全基因组的转录.
- 采用染色体免疫沉测序 (ChIP-seq) 来绘制基因素修饰和转录因子结合位点的地图.
- 检查了T细胞承诺的五个不同的阶段.
主要成果:
- 鉴定了参与T细胞发育的促进器-远端调节元件.
- 揭示了各种压制机制,使替代血统的基因沉默.
- 观察到动态和可逆的组织蛋白修饰,压制性标记往往落后于转录性变化.
- 根据表观遗传标记,剂量和发育背景,证明了GATA-3和PU.1的特定因素招募规则.
结论:
- GATA-3和PU.1的结合取决于环境,受表观遗传环境的影响.
- 表观遗传修饰在T细胞结合期间调节基因表达方面发挥着动态作用.
- 这项研究提供了对T细胞谱系规范复杂分子控制的见解.
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