小柯机器人

研究阐明脊椎动物进化过程
2021-01-20 17:00

德国维尔茨堡大学Manfred Schartl、汉堡大学Thorsten Burmester、康斯坦茨大学Axel Meyer以及奥地利校园-维也纳-生物中心分子病理研究所(IMP)Elly M. Tanaka、维也纳大学Oleg Simakov团队合作取得最新进展。他们发现巨型肺鱼基因组揭示了脊椎动物对土地的征服。这一研究成果发表在2021年1月18日的国际学术期刊《自然》上。

他们确定了最大的染色体质量的动物基因组,澳大利亚的肺鱼、新角鲨。它的巨大体积(约为人类的14倍)主要归因于巨大的基因间区域和具有高重复含量(约90%)的内含子,其组成比射线鳍鱼更像四足动物(主要是LINE元件)。与巨大的salamander基因组相比,肺鱼基因组继续独立地并且通过不同的机制进行扩张(其TEs仍然活跃)。保留了与17个完全组装的大染色体的其他脊椎动物染色体同等的地位,就像所有微染色体与祖先脊椎动物核型的保守古代同源性一样。

系统生物学分析确定,肺鱼作为四足动物亲缘关系最近的物种,在进化中处于关键位置,这突显了它们对于了解与陆地化相关的创新的重要性。适应陆地生活的方式包括在其裂片中获得像hoxc13和sall1这样的发育基因的肢体状表达。与专性呼吸相关的基因(例如肺表面活性剂)的进化和重复速率提高,并且检测空气中异味的气味受体基因家族的扩展也有助于它们形成四足动物状生物学。这些发现促进了人们对脊椎动物进化过程中这一主要转变的理解。

据悉,肺鱼属于叶鳍鱼(Sarcopterygii),在泥盆纪“被征服”的土地上,导致了所有陆地脊椎动物的产生,包括人类。

附:英文原文

Title: Giant lungfish genome elucidates the conquest of land by vertebrates

Author: Axel Meyer, Siegfried Schloissnig, Paolo Franchini, Kang Du, Joost Woltering, Iker Irisarri, Wai Yee Wong, Sergej Nowoshilow, Susanne Kneitz, Akane Kawaguchi, Andrej Fabrizius, Peiwen Xiong, Corentin Dechaud, Herman Spaink, Jean-Nicolas Volff, Oleg Simakov, Thorsten Burmester, Elly M. Tanaka, Manfred Schartl

Issue&Volume: 2021-01-18

Abstract: Lungfishes belong to lobe-fined fish (Sarcopterygii) that in the Devonian ‘conquered’ land and gave rise to all land vertebrates, including humans1–3. We determined the largest chromosome-quality animal genome, the Australian lungfish, Neoceratodus forsteri. Its vast size (~14x of human) is attributable mostly to huge intergenic regions and introns with high repeat content (≈90%) whose components resemble tetrapods more (mostly LINE elements) than ray-finned fish. The lungfish genome continues to expand (its TEs are still active) independently and by different mechanisms than enormous salamander genomes. Synteny to other vertebrate chromosomes of 17 fully assembled macrochromosomes is maintained just as its conserved ancient homology of all microchromosomes to the ancestral vertebrate karyotype. Phylogenomic analyses ascertained that lungfish occupy an evolutionary key-position as closest living relatives to tetrapods, underscoring their importance for understanding innovations associated with terrestrialization4,5. Preadaptations to living on land include gaining of limb-like expression of developmental genes such as hoxc13 and sall1 in their lobed fins. Increased rates of evolution and duplication of genes associated with obligate air-breathing such as lung surfactants and the expansion of odorant receptor gene-families that detect airborne odours contribute to their tetrapod-like biology. These findings advance our understanding of this major transition during vertebrate evolution.

DOI: 10.1038/s41586-021-03198-8

Source: https://www.nature.com/articles/s41586-021-03198-8

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:69.504
官方网址:http://www.nature.com/
投稿链接:http://www.nature.com/authors/submit_manuscript.html


本期文章:《自然》:Online/在线发表

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