Fujian Key Laboratory of Developmental and Neural Biology & Southern Center for Biomedical Research, College of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China.
Universidade Federal Rural da Amazônia (UFRA) Laboratório de Reprodução Animal (LABRAC), Parauapebas, PA, Brazil.
Nat Commun. 2022 Feb 17;13(1):944. doi: 10.1038/s41467-022-28585-1.
The karyotype of most birds has remained considerably stable during more than 100 million years' evolution, except for some groups, such as parrots. The evolutionary processes and underlying genetic mechanism of chromosomal rearrangements in parrots, however, are poorly understood. Here, using chromosome-level assemblies of four parrot genomes, we uncover frequent chromosome fusions and fissions, with most of them occurring independently among lineages. The increased activities of chromosomal rearrangements in parrots are likely associated with parrot-specific loss of two genes, ALC1 and PARP3, that have known functions in the repair of double-strand breaks and maintenance of genome stability. We further find that the fusion of the ZW sex chromosomes and chromosome 11 has created a pair of neo-sex chromosomes in the ancestor of parrots, and the chromosome 25 has been further added to the sex chromosomes in monk parakeet. Together, the combination of our genomic and cytogenetic analyses characterizes the complex evolutionary history of chromosomal rearrangements and sex chromosomes in parrots.
除了一些鸟类群体（如鹦鹉）之外，大多数鸟类的核型在超过 1 亿年的进化过程中保持相当稳定。然而，鹦鹉染色体重排的进化过程和潜在遗传机制仍知之甚少。在这里，我们使用四个鹦鹉基因组的染色体水平组装，揭示了频繁的染色体融合和裂变，其中大多数发生在谱系之间是独立的。鹦鹉中染色体重排活动的增加可能与 ALC1 和 PARP3 这两个基因的特异性缺失有关，这两个基因在修复双链断裂和维持基因组稳定性方面具有已知的功能。我们进一步发现，ZW 性染色体与 11 号染色体的融合在鹦鹉祖先中创造了一对新的性染色体，而 25 号染色体在和尚鹦鹉中进一步添加到性染色体中。总的来说，我们的基因组和细胞遗传学分析结合起来，描绘了鹦鹉中染色体重排和性染色体的复杂进化历史。
