突然和大规模的转子子放大对大米基因表达的意外后果
Ken Naito1, Feng Zhang, Takuji Tsukiyama
1Department of Plant Biology, University of Georgia, Athens, Georgia 30602, USA.
Nature
|October 23, 2009
概括
像mPing这样的可转移元素可以在米基因组中迅速增加. 大多数插入对基因表达进行上调或没有影响,有些则创建新的压力诱导调节网络.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 植物科学 植物科学
背景情况:
- 可转移元素 (TE) 在真核生物基因组中很丰富,并推动了进化.
- 快速的TE爆发对宿主基因组生存构成挑战,但很难研究.
- 已经观察到,大米中的DNA转位子mPing每一代显著增加拷贝数.
研究的目的:
- 为了研究高副本数量的可转移元素插入对大米宿主基因组进化的影响.
- 分析mPing插入对邻近基因的转录效应.
- 了解基因组耐受或适应TE增殖的机制.
主要方法:
- 利用完全测序的米基因组,通过24个单个植物的高通量测序确定了1,664个mPing插入位.
- 通过比较微阵列分析,评估了这些插入对710个基因的基因表达的影响.
- 检查了插入部位偏好及其与基因调节变化的相关性.
主要成果:
- 大多数mPing插入导致基因上调或对转录没有可检测的影响.
- mPing插入显示了对5'侧边区域的偏好,避免了exons.
- 一个mPing插入子集产生了新的调节网络,使相邻基因具有应激诱导性.
结论:
- 主体基因组可以容纳快速的可转移元素爆发与适度的转录破坏.
- mPing的插入偏好影响其对基因调节的影响.
- 可转移的元素有助于基因组重组和基因调节网络的演变,包括应激反应.
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