Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, 9190401 Jerusalem, Israel.
Mol Biol Evol. 2024 May 3;41(5). doi: 10.1093/molbev/msae082.
Gene duplication is a major force driving evolutionary innovation. A classic example is generating new animal toxins via duplication of physiological protein-encoding genes and recruitment into venom. While this process drives the innovation of many animal venoms, reverse recruitment of toxins into nonvenomous cells remains unresolved. Using comparative genomics, we find members of the Membrane Attack Complex and Perforin Family (MAC) have been recruited into venom-injecting cells (cnidocytes), in soft and stony corals and sea anemones, suggesting that the ancestral MAC was a cnidocyte expressed toxin. Further investigation into the model sea anemone Nematostella vectensis reveals that three members have undergone Nematostella-specific duplications leading to their reverse recruitment into endomesodermal cells. Furthermore, simultaneous knockdown of all three endomesodermally expressed MACs leads to mis-development, supporting that these paralogs have nonvenomous function. By resolving the evolutionary history and function of MACs in Nematostella, we provide the first proof for reverse recruitment from venom to organismal development.
基因复制是推动进化创新的主要力量。一个经典的例子是通过复制生理蛋白编码基因并将其招募到毒液中来产生新的动物毒素。虽然这个过程推动了许多动物毒液的创新，但毒素向非毒液细胞的反向招募仍未解决。通过比较基因组学，我们发现膜攻击复合物和穿孔素家族（MAC）的成员已被招募到分泌毒液的细胞（刺胞动物）中，包括软珊瑚和石珊瑚以及海葵中，这表明原始 MAC 是一种表达在刺胞动物中的毒素。对模式海葵 Nematostella vectensis 的进一步研究表明，有三个成员经历了 Nematostella 特异性复制，导致它们反向招募到内胚层和中胚层细胞。此外，同时敲低所有三个内胚层和中胚层表达的 MAC 会导致发育异常，支持这些旁系同源物具有非毒液功能。通过解决 Nematostella 中 MAC 的进化历史和功能，我们首次证明了从毒液到生物体发育的反向招募。
