人类基因组中中心转变区域的结构和演变
Xinwei She1, Julie E Horvath, Zhaoshi Jiang
1Department of Genetics, Center for Computational Genomics and the Center for Human Genetics, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, Cleveland, Ohio 44106, USA.
Nature
|August 20, 2004
概括
人类的周心膜区域含有转移的 euchromatic DNA,主要在丸中形成新的转录. 这就解释了中心变态过渡区域的组织和进化.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 中心转变区域对于染色体结构和功能至关重要.
- 它们的序列上下文很难用基因组序列草案来解决.
研究的目的:
- 分析人类周心区域的结构和组合.
- 了解这些地区DNA重复的起源和影响.
主要方法:
- 详细分析了5个大数据库的人类周心区域的详细分析.
- 检查转录多样性和染色体间重复.
- 追踪DNA转换事件的进化历史.
主要成果:
- 大多数染色体臂都表现出转录多样性下降的梯度和在中间体附近增加的重复.
- 大约30%的中间体过渡区域来自转移的 euchromatic 基因段.
- 在灵长类动物进化过程中,DNA转移发生在每百万年6-7次.
- 至少有28个新的转录通过外取和混合产生,其中许多是丸特异的.
结论:
- 双重转换的 euchromatic DNA 显著塑造了周围中心的区域.
- 这个过程产生了新的转录,并为基因组进化做出了贡献.
- 特定的周心膜区域作为优选的网站,用于euchromatic DNA的整合.
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