Department of Biology, Miami University, Oxford, OH, USA.
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Nat Ecol Evol. 2020 Dec;4(12):1694-1702. doi: 10.1038/s41559-020-1257-8. Epub 2020 Aug 3.
The origin of insect wings is a biological mystery that has fascinated scientists for centuries. Identification of tissues homologous to insect wings from lineages outside of Insecta will provide pivotal information to resolve this conundrum. Here, through expression and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) functional analyses in Parhyale, we show that a gene network similar to the insect wing gene network (preWGN) operates both in the crustacean terga and in the proximal leg segments, suggesting that the evolution of a preWGN precedes the emergence of insect wings, and that from an evo-devo perspective, both of these tissues qualify as potential crustacean wing homologues. Combining these results with recent wing origin studies in insects, we discuss the possibility that both tissues are crustacean wing homologues, which supports a dual evolutionary origin of insect wings (that is, novelty through a merger of two distinct tissues). These outcomes have a crucial impact on the course of the intellectual battle between the two historically competing wing origin hypotheses.
昆虫翅膀的起源是一个令科学家们着迷了几个世纪的生物学谜题。鉴定出昆虫纲以外的谱系中与昆虫翅膀同源的组织，将为解决这个难题提供关键信息。在这里，我们通过 Parhyale 中的表达和成簇规律间隔短回文重复 (CRISPR)-CRISPR 相关蛋白 9 (Cas9) 功能分析表明，一个类似于昆虫翅膀基因网络 (preWGN) 的基因网络既在甲壳动物背板中运作，也在近端附肢节段中运作，这表明 preWGN 的进化先于昆虫翅膀的出现，并且从进化发育的角度来看，这两种组织都可以作为潜在的甲壳动物翅膀同源物。将这些结果与昆虫翅膀起源的最新研究结合起来，我们讨论了这两种组织都可能是甲壳动物翅膀同源物的可能性，这支持了昆虫翅膀的双重进化起源（即通过两种不同组织的融合产生新颖性）。这些结果对两个历史上相互竞争的翅膀起源假说之间的智力斗争进程产生了至关重要的影响。
