Duplication and Adaptive Evolution of a Key Centromeric Protein in Mimulus, a Genus with Female Meiotic Drive
Duplication and Adaptive Evolution of a Key Centromeric Protein in Mimulus, a Genus with Female Meiotic Drive
复制标题
具有雌性减数分裂驱动力的酸浆菌属中关键着丝粒蛋白的复制和适应性进化
DOI：
10.1093/molbev/msv145
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发表时间：
2015-10-01
影响因子：
10.7
通讯作者：
Fishman, Lila
中科院分区：
文献类型：
--
作者：
Finseth, Findley R.;Dong, Yuzhu;Fishman, Lila
雌性减数分裂的基本不对称性为遗传元件创造了一个竞技场，以竞争包含在卵子中，促进着丝粒变体的自私进化，最大限度地将其传递到未来的卵子。这种“女性减数分裂驱动”被假设用来解释着丝粒DNA和蛋白质的矛盾复杂和快速进化的性质。尽管理论上广泛存在，但很少观察到主动驱动的情况，从而限制了直接评估着丝粒驱动对着丝粒和结合蛋白分子变异的影响的机会。在这里，我们的特点CENH 3，着丝粒定义的组蛋白变体的分子进化模式，在Mimulus monkeyflowers，一个属与少数已知的情况下，积极的着丝粒相关的女性减数分裂驱动器。首先，我们在二倍体Mimulus中发现了一种新的CENH 3重复，包括具有主动驱动着丝粒的谱系。第二，我们证明了CENH 3的N-末端的几个位点的长期适应性进化，CENH 3是一个具有减数分裂特异性功能的区域，puronectin与着丝粒DNA相互作用。最后，我们推断，旁系同源物在不同的选择制度下发展，在N-末端的一些网站在正向选择下的前直系同源物或只有一个paradigs（CENH3_B）和旁系同源物表现出显着不同的模式的多态性人口。我们在CENH 3中发现的与着丝粒相关的减数分裂驱动的长期适应性进化支持了着丝粒DNA和结合蛋白之间的进化优势的对抗性、共同进化的斗争。
The fundamental asymmetry of female meiosis creates an arena for genetic elements to compete for inclusion in the egg, promoting the selfish evolution of centromere variants that maximize their transmission to the future egg. Such "female meiotic drive" has been hypothesized to explain the paradoxically complex and rapidly evolving nature of centromeric DNA and proteins. Although theoretically widespread, few cases of active drive have been observed, thereby limiting the opportunities to directly assess the impact of centromeric drive on molecular variation at centromeres and binding proteins. Here, we characterize the molecular evolutionary patterns of CENH3, the centromere-defining histone variant, in Mimulus monkeyflowers, a genus with one of the few known cases of active centromere-associated female meiotic drive. First, we identify a novel duplication of CENH3 in diploid Mimulus, including in lineages with actively driving centromeres. Second, we demonstrate long-term adaptive evolution at several sites in the N-terminus of CENH3, a region with some meiosis-specific functions that putatively interacts with centromeric DNA. Finally, we infer that the paralogs evolve under different selective regimes; some sites in the N-terminus evolve under positive selection in the pro-orthologs or only one paralog (CENH3_B) and the paralogs exhibit significantly different patterns of polymorphism within populations. Our finding of long-term, adaptive evolution at CENH3 in the context of centromere-associated meiotic drive supports an antagonistic, coevolutionary battle for evolutionary dominance between centromeric DNA and binding proteins.