论文标题：Cassiosomes are stinging-cell structures in the mucus of the upside-down jellyfish Cassiopea xamachana

期刊：Communications Biology

作者：Cheryl L. Ames, Anna M. L. Klompen et.al

发表时间：2020/02/13

数字识别码：10.1038/s42003-020-0777-8

微信链接：点击此处阅读微信文章

根据《通讯-生物学》发表的一篇论文Cassiosomes are stinging-cell structures in the mucus of the upside-down jellyfish Cassiopea xamachana，科学家在倒立水母（Cassiopea xamachana, 仙女水母属）的粘液中发现了刺细胞形成的新结构，这种被称为cassiosome 的结构不仅能帮助水母捕食猎物，或许还是浮浅者在红树林水域接触到“有刺痛感的水”的原因。

图片来源：Allen Collins

红树林是仙女水母属（Cassiopea）的生活家园，这些仙女水母会上下颠倒地停留在浅海海底，褶皱状的口腕朝上。长期以来，佛罗里达、加勒比地区和密克罗尼西亚周围水域的浮浅者一直报告称，他们在没有和任何水母有直接接触的情况下，感觉自己被水母蜇到。研究人员提出了许多水中刺感的可能来源，但确切原因却一直未知。

美国海军研究实验室生物/分子科学与工程中心的Gary Vora和同事查阅了20世纪早期以来关于仙女水母属的科学文献，寻找与这种刺感有关的线索。作者了解到，仙女水母属释放的粘液含有非常微小的细胞团，名为cassiosome。作者利用显微镜发现，这些cassiosome的外膜层排列有成千上万个水母刺细胞。这些刺细胞被称为刺胞，是一种含有毒液的囊，一般存在于水母触手的特定细胞中。作者的研究表明，水母会像扔迷你手榴弹一样，把这些充满了cassiosome的粘液释放到海水中，让周围的水体产生刺感。作者在其他四种相关的水母中也发现了这些cassiosome。

摘要：Snorkelers in mangrove forest waters inhabited by the upside-down jellyfish Cassiopea xamachana report discomfort due to a sensation known as stinging water, the cause of which is unknown. Using a combination of histology, microscopy, microfluidics, videography, molecular biology, and mass spectrometry-based proteomics, we describe C. xamachana stinging-cell structures that we term cassiosomes. These structures are released within C. xamachanamucus and are capable of killing prey. Cassiosomes consist of an outer epithelial layer mainly composed of nematocytes surrounding a core filled by endosymbiotic dinoflagellates hosted within amoebocytes and presumptive mesoglea. Furthermore, we report cassiosome structures in four additional jellyfish species in the same taxonomic group as C. xamachana (Class Scyphozoa; Order Rhizostomeae), categorized as either motile (ciliated) or nonmotile types. This inaugural study provides a qualitative assessment of the stinging contents of C. xamachana mucus and implicates mucus containing cassiosomes and free intact nematocytes as the cause of stinging water.

来源：科学网