在玉米化过程中选择的极限
Nature
|March 27, 1999
概括
玉米化涉及选择喜欢的特征,但遗传多样性得到了维护. 选择主要影响了theosinte分支1基因的调节区域,而不是其蛋白质编码区域.
科学领域:
- 植物遗传学 植物遗传学
- 农作物化 农作物化
- 进化生物学是进化的生物学.
背景情况:
- 农作物化,发生在1万年前,涉及古代农业家的人工选择.
- 在化过程中强有力的选择可以显著减少作物的遗传多样性.
- 神分支1 (tb1) 基因在玉米的进化和化中起着至关重要的作用.
研究的目的:
- 研究玉米化过程中选择对遗传多样性的影响.
- 分析tb1基因内的核酸多态性,以了解选择的影响.
- 为了确定选择是否影响了 tb1.1 的调节或蛋白质编码区域.
主要方法:
- 在theosinte分支1基因中检查了核酸多态性.
- 分析了 tb1.1 的调节和蛋白质编码区域的选择模式.
- 比较玉米及其野生祖先的遗传多样性.
主要成果:
- 选择效应仅限于tb1的调节区域,而不是蛋白质编码区域.
- 尽管有强烈的选择,但高的重组率和漫长的化时期可能保留了遗传多样性.
- 玉米表现出显著的遗传变异性,与选择对其蛋白质编码基因的影响有限一致.
结论:
- 玉米的化需要几个世纪的时间,主要涉及到关键基因的调节元件的选择,如tb1.
- 玉米的化起源于墨西哥西南部的Balsas teosinte.
- 了解选择模式是解释作物变异性和进化历史的关键.
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