黄羽毛颜色的基因映射和生物化学基础
Thomas F Cooke1, Curt R Fischer2, Ping Wu3
1Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
Cell
|October 7, 2017
概括
科学家发现了蓝色鸟羽毛的基因. MuPKS基因的突变阻止了黄色颜料的产生,揭示了对颜色进化的洞察力.
科学领域:
- 鸟类遗传学
- 生物化学
- 进化生物学
背景情况:
- 的羽毛呈现出多种鲜的颜色,包括红色,色和黄色,
- 一个多世纪以来,鸟 (Melopsittacus undulatus) 已经被选择性地养为羽毛变异,但遗传基础仍然难以捉摸.
研究的目的:
- 确定鸟中蓝色羽毛特征的遗传基础,这种特征在于没有黄色色素.
- 了解在中皮肤色素产生背后的分子机制.
主要方法:
- 全基因组协会映射以定位对蓝色特征负责的遗传位点.
- 基因表达分析以调查候选基因在色素生产中的作用.
- 在酵母中确定基因的异质表达,以确认色素合成.
- 质谱分析合成颜料的化学结构.
主要成果:
- 蓝色羽毛特征被映射到单核酸多态 (SNP) 中,导致多基酸合成基因 (MuPKS) 中的R644W氨基酸替代.
- 酵母中MuPKS的异质表达导致了与羽毛中发现的黄色颜料相同的积累.
- 通过R644W替代,可以消除MuPKS的酶活性,从而防止黄色色素的形成.
- 基因表达的比较数据表明,的进化色彩多样化是由影响羽毛表皮中的MuPKS表达水平的调节性变化驱动的.
结论:
- 该研究确定MuPKS是负责合成中的黄色psittacofulvin色素的关键酶.
- MuPKS的一种特定突变 (R644W) 导致黄色素的丧失,导致鸟的羽毛变成蓝色.
- 这些发现为了解的自然颜色变化提供了分子基础,并强调了基因调节在羽毛色彩进化中的作用.
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