微RNA是经典进化热点基因的效应基因
Shen Tian1, Yoshimasa Asano2,3, Tirtha Das Banerjee1
1Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.
概括
一种微RNA,mir-193,驱动了蝶和蝶的黑色翅膀色彩演变. 这种小RNA来源于一个名为象牙的长非编码RNA, 抑制色素基因, 揭示了适应性进化的新机制.
科学领域:
- 进化遗传学
- 发育生物学
- 分子遗传学
背景情况:
- 在Lepidoptera的皮质基因附近的基因组区域是黑色翼色进化的热点.
- 尽管进行了广泛的研究,但对这种适应性特征负责的特定基因仍然未被确定.
研究的目的:
- 在类动物皮层内确定调节黑色翅膀颜色演变的效应基因.
- 在其他物种中研究这种效应物的保存作用,例如Drosophila.
主要方法:
- 在Lepidoptera中的皮质位点的比较基因组学分析.
- 测试候选基因和微RNA的作用的功能性测试.
- 用RNA测序来识别调节元件及其目标.
主要成果:
- 包括皮质在内的四个蛋白质编码基因都没有被确定为主要的效应因子.
- 一个名为mir-193的微RNA被确定为调节不同蝶系的黑色色素的关键效应因子.
- mir-193是由一个大型的原始非编码RNA,象牙,并通过抑制色素基因的功能.
- 在Drosophila中保留了mir-193在色素的功能.
结论:
- 微RNA mir-193 是类动物适应性黑色翅膀色彩演变的主要驱动因素.
- 这一发现突显了非编码RNA在进化过程中的重要作用.
- 这项研究表明,微RNA可以反复驱动动物的适应性进化.
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