Parrot Genomes and the Evolution of Heightened Longevity and Cognition
Parrot Genomes and the Evolution of Heightened Longevity and Cognition
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DOI：
10.1016/j.cub.2018.10.050
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发表时间：
2018-12-17
期刊：
影响因子：
9.2
通讯作者：
Mello, Claudio V.
中科院分区：
文献类型：
--
作者：
Wirthlin, Morgan;Lima, Nicholas C. B.;Mello, Claudio V.
鹦鹉是鸟类中最独特、最有趣的一群，它们的大脑高度膨胀，认知能力和声音交流能力高度发达，与其他类似大小的鸟类相比，它们的寿命更长。然而，这些特征的遗传基础在很大程度上仍未被确定。为了解决这个问题，我们制作了一个高覆盖率的、带注释的亚马逊蓝额鸟（Amazona aestiva）基因组汇编，并与其他30种鸟类进行了广泛的比较分析，其中包括4种鹦鹉。我们发现了鹦鹉特有的几个基因组特征，包括鹦鹉特有的新基因和鹦鹉对现有基因编码和调控序列的特异性修饰。我们还发现了鹦鹉和其他长寿鸟类在强选择下的基因组特征，包括先前与寿命决定相关的基因以及数百个新的候选基因。这些基因支持一系列细胞功能，包括端粒酶活性；DNA损伤修复；细胞增殖、肿瘤和免疫的控制；以及抗氧化机制。我们还发现了大脑表达的、特定于鹦鹉的类似物，它们在神经发育或声音学习大脑回路中具有已知的功能。有趣的是，鹦鹉在保守调控序列上的特异性变化绝大多数与与认知能力相关的基因有关，并且在人类谱系中经历了类似的选择，这表明趋同进化。这些发现为长寿和认知的遗传和进化提供了新的见解，也为探索这些特征的机制基础提供了新的目标。
Parrots are one of the most distinct and intriguing groups of birds, with highly expanded brains [1], highly developed cognitive [2] and vocal communication [3] skills, and a long lifespan compared to other similar-sized birds [4]. Yet the genetic basis of these traits remains largely unidentified. To address this question, we have generated a high-coverage, annotated assembly of the genome of the blue-fronted Amazon (Amazona aestiva) and carried out extensive comparative analyses with 30 other avian species, including 4 additional parrots. We identified several genomic features unique to parrots, including parrot- specific novel genes and parrot-specific modifications to coding and regulatory sequences of existing genes. We also discovered genomic features under strong selection in parrots and other long-lived birds, including genes previously associated with lifespan determination as well as several hundred new candidate genes. These genes support a range of cellular functions, including telomerase activity; DNA damage repair; control of cell proliferation, cancer, and immunity; and anti-oxidative mechanisms. We also identified brain-expressed, parrot-specific paralogs with known functions in neural development or vocal-learning brain circuits. Intriguingly, parrotspecific changes in conserved regulatory sequences were overwhelmingly associated with genes that are linked to cognitive abilities and have undergone similar selection in the human lineage, suggesting convergent evolution. These findings bring novel insights into the genetics and evolution of longevity and cognition, as well as provide novel targets for exploring the mechanistic basis of these traits.