一个远端增强子和一个超保守的外子是由一个新型的逆位子衍生出来的
Gill Bejerano1, Craig B Lowe, Nadav Ahituv
1Center for Biomolecular Science and Engineering, University of California Santa Cruz, Santa Cruz, California 95064, USA. jill@soe.ucsc.edu
Nature
|April 21, 2006
概括
高度保存的脊椎动物基因组区域起源于古代的Sarcopterygian短间隔重复元素 (SINEs). 这些4亿多年前活跃的回形子被抽取到调节元件中,并交替拼接出外形子,揭示了它们的进化起源.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 分子生物学分子生物学
背景情况:
- 脊椎动物的基因组含有众多高度保存的 cis 调节元素,但它们的进化起源,特别是无脊椎动物,仍然在很大程度上是未知的.
- 比较基因组学预测了数千个更保守的区域,但它们的祖先序列通常无法通过序列相似性来追踪.
研究的目的:
- 研究四足动物基因组中保存的非编码区域的进化起源.
- 为了确定高度保存的脊椎动物特定基因组序列的来源.
主要方法:
- 比较基因组学来追踪跨物种的保护区域.
- 一个新的短间隔重复元素 (SINE) 逆转子家族的识别和特征.
- 使用小鼠增强剂测试来测试调节活动的功能分析.
- 序列分析用于识别基因内的替代拼接的前子.
主要成果:
- 四足动物中保存的非编码区域的一类起源于至少4.1亿年前活跃的Sarcopterygian特定的SINE家族.
- 一个SINE衍生的元素作为神经发育基因ISL1.1的增强剂.
- 在PCBP2等基因中,其他SINE副本已被取出作为替代拼接的外基因,包括一个超保守的区域.
结论:
- 可转移的元素,特别是SINEs,可以被抽取到功能性基因组元素中,从而为脊椎动物的保存序列做出贡献.
- 这项研究为高度保守的脊椎动物特异性基因组序列的子集提供了新的起源.
- 这些发现突显了重复元素和宿主基因组之间的动态进化相互作用.
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