随机过程和进化速率的变化与热带硬松 (Pinus) 的血统中的多样化有关
Jorge Cruz-Nicolás1, Juan Pablo Jaramillo-Correa2, David S Gernandt1
1Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México CDMX 04510, Mexico.
Molecular phylogenetics and evolution
|January 9, 2024
概括
针叶树的分子进化是复杂的,因为古代的多态. 这项研究揭示了随机过程和潜在的积极选择推动了北美和中美洲硬松树的多样化.
科学领域:
- 进化生物学 进化生物学
- 人口遗传学 人口遗传学
- 分子进化分子进化
背景情况:
- 了解物种多样化需要研究多态性和分子进化,特别是在具有古老多态性的缓慢进化的针叶树中.
- 针叶树由于进化速度缓慢,生命周期长,共享多态,从而对多样化驱动因素的研究构成挑战.
- 逐步迁移模型预测选择效率和遗传结构的临床模式,可能受到环境变化和积极选择的影响.
研究的目的:
- 推断多态化模式,净化选择效率和硬松系中的分子进化.
- 在分子指数和形态特征中调查潜在的临床模式.
- 识别推动物种分歧的积极选择信号,特别是在对环境差异的反应中.
主要方法:
- 分析了161个核基因 (约. 71 Kb) 来自北美,加勒比海,墨西哥和中美洲的硬松树.
- 估计了分子进化指数 (Ka,Ks,Ka/Ks,dN,dS,dN/dS,dxy) 并将它们与五个类别进行了比较.
- 研究了分子指数和形态特征 (针长度,长度) 的临床模式,并推断了遗传结构和环境差异.
主要成果:
- 在分类群中发现了分子进化指数 (Ka,Ks,Ka/Ks) 的差异,在埃利奥蒂和帕图拉分类群中注意到了放松的净化选择.
- 环境差异与地理距离和类型相关,表明有不同的选择性压力.
- 索引Ks,dxy和针的长度显示了地理关系,而排卵孔的长度没有.
结论:
- 大多数分析的基因都在进行净化选择,但一些松树种的更快的进化速率表明,积极的选择可能导致了分歧.
- 随机过程在这种硬松群体的多样化中发挥了重要作用.
- 积极的选择可能影响了墨西哥和中美洲松树的分歧.
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