2025年8月13日出版的《自然》杂志发表了伦敦大学学院Ferdinand Marlétaz小组的最新成果，他们的研究开发出了毛颚动物独特体型结构的基因组起源。

在这里，研究组从基因组、调控和细胞水平研究了最独特的动物门之一毛颚动物的起源，毛颚动物的有机体特征在历史上使其系统发育定位复杂化。研究人员发现，这些特征在细胞类型水平上通过起源于毛颚纲谱系的基因表达反映出来，有助于在感觉和结构水平上适应浮游生物。与食颌目的其他成员（也包括轮虫和其他几个微观门）类似，毛颌目经历了基因丢失和染色体突变的加速基因组进化。

此外，它们在没有全基因组复制证据的情况下，二次复制了基因的末端，例如，产生了串联扩增的Hox基因以及许多门特异性基因。该团队还检测到富含重复的高度甲基化的新中心粒和一个简化的DNA甲基化工具包，该工具包涉及移动元件抑制而不是转录控制。与化石证据一致，他们的观察结果表明，毛颚动物是在经过一个形态简化阶段后出现的，这个阶段是通过器官系统的重塑和大规模的基因组重组来实现的，这解释了它们身体结构的独特性。

研究人员表示，动物门的出现是动物生命史上的一个快速事件，每个门都有自己独特的身体结构，但其基因组基础仍然知之甚少。

附：英文原文

Title: The genomic origin of the unique chaetognath body plan

Author: Piovani, Laura, Gavriouchkina, Daria, Parey, Elise, Sarre, Luke A., Peijnenburg, Katja T. C. A., Martn-Durn, Jos Mara, Rokhsar, Daniel S., Satoh, Noriyuki, de Mendoza, Alex, Goto, Taichiro, Marltaz, Ferdinand

Issue&Volume: 2025-08-13

Abstract: The emergence of animal phyla, each with their unique body plan, was a rapid event in the history of animal life, yet its genomic underpinnings are still poorly understood1. Here we investigate at the genomic, regulatory and cellular levels, the origin of one of the most distinctive animal phyla, the chaetognaths, whose organismal characteristics have historically complicated their phylogenetic placement2,3. We show that these characteristics are reflected at the cell-type level by the expression of genes that originated in the chaetognath lineage, contributing to adaptation to planktonic life at the sensory and structural levels4. Similarly to other members of gnathiferans (which also include rotifers and several other microscopic phyla)5,6, chaetognaths have undergone accelerated genomic evolution with gene loss and chromosomal fusions7,8. Furthermore, they secondarily duplicated thousands of genes9,10, without evidence for a whole-genome duplication, yielding, for instance, tandemly expanded Hox genes, as well as many phylum-specific genes. We also detected repeat-rich highly methylated neocentromeres and a simplified DNA methylation toolkit that is involved in mobile element repression rather than transcriptional control. Consistent with fossil evidence11,12, our observations suggest that chaetognaths emerged after a phase of morphological simplification through a reinvention of organ systems paralleled by massive genomic reorganization, explaining the uniqueness of their body plan.

DOI: 10.1038/s41586-025-09403-2

Source: https://www.nature.com/articles/s41586-025-09403-2