在小鼠中,基因重组是远离功能性基因组元素的
Kevin Brick1, Fatima Smagulova, Pavel Khil
1National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, Maryland 20892, USA.
Nature
|June 5, 2012
概括
PRDM9蛋白通常将基因重组指向特定的热点. 在缺少它的情况下,重组仍然发生,但被重新定向到基因促进器和其他基因组位点.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 生殖生物学 生殖生物学
背景情况:
- 介质变异过程中的遗传重组对于子体生成和物种化至关重要.
- 含有9的PR域 (PRDM9) 是一种与哺乳动物重组和物种化相关的基因组甲基转移酶.
- 据信PRDM9的指域通过序列特定的结合来指定重组热点.
研究的目的:
- 在Prdm9淘汰赛小鼠和不同小鼠菌株中绘制和分析重组启动位点的全基因组分布.
- 阐明PRDM9在确定重组热点位置方面的作用.
- 了解PRDM9独立重组的机制.
主要方法:
- 重组启动地点的全基因组映射.
- 对Prdm9淘汰赛小鼠,具有不同等位基的野生类型小鼠和F(1) 杂交物中的重组模式的分析.
- 在重组位点检查质子修饰,特别是H3K4三甲基化.
主要成果:
- PRDM9决定了几乎所有哺乳动物重组热点的位置,除了伪自带区域 (PAR).
- 在Prdm9淘汰赛小鼠中,重组热点仍然存在,它们位于H3K4三甲基化标记处.
- 在没有PRDM9的情况下,重组主要在促进体和其他PRDM9独立的H3K4三甲基化位点开始.
结论:
- 在小鼠基因组中,PRDM9是重组热点位置的主要决定因素.
- PRDM9在防止基因促进体和功能性基因组元素的重组中发挥了意想不到的作用.
- 这项研究揭示了PRDM9的新功能,即引导重组离重要的调节区域.
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