单核细胞前启动复合体的全基因组结构和组织
Ho Sung Rhee1, B Franklin Pugh
1Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Nature
|January 20, 2012
概括
研究人员使用ChIP-exo.exo精确地绘制了全基因组的转录前启动复合体 (PICs). 这揭示了PICs.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 生物化学 生物化学
背景情况:
- 转录前启动复合体 (PIC) 对于基因调控至关重要.
- PICs的全基因组结构和位置组织在很大程度上仍然没有特征.
- 了解PIC组织对于破译基因表达控制至关重要.
研究的目的:
- 精确地绘制转录前启动复合体 (PIC) 的基因组位置.
- 调查真核基因组中PIC的位置约束和组织原则.
- 探索PICs,核细胞和转录起点之间的关系.
主要方法:
- 兰巴外核酶应用于染色体免疫沉物 (ChIP-exo) 进行高分辨率映射.
- 在Saccharomyces中对6,045个PIC进行基因组分析.
- 将ChIP-exo数据与晶体学模型和核细胞定位信息集成.
主要成果:
- 包括RNA聚合酶II和相关因子在内的PIC被精确地定位在促进体内,并被排除在编码区域之外.
- ChIP-exo模式准确地识别了TATA-like元素在TATA-less主办方.
- PIC和转录开始地点受到下游+1核细胞体的限制,在TATA-box促进者中观察到竞争.
结论:
- 在转录开始地点,PICs表现出相对于细胞核相对的局限位置组织.
- 核细胞的定位影响PIC参与和潜在的转录开始地点的选择.
- 对PIC的基因组映射有助于区分真正的基因与转录噪声.
相关概念视频
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Overview
Histone Variants at the Centromere
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3 variants are also...


