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Title: Cassiosomes are stinging-cell structures in the mucus of the upside-down jellyfish Cassiopea xamachana
Abstract

Snorkelers in mangrove forest waters inhabited by the upside-down jellyfishCassiopea xamachanareport 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 describeC. xamachanastinging-cell structures that we term cassiosomes. These structures are released withinC. 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 asC. xamachana(Class Scyphozoa; Order Rhizostomeae), categorized as either motile (ciliated) or nonmotile types. This inaugural study provides a qualitative assessment of the stinging contents ofC. xamachanamucus and implicates mucus containing cassiosomes and free intact nematocytes as the cause of stinging water.

 
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NSF-PAR ID:
10154196
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Communications Biology
Volume:
3
Issue:
1
ISSN:
2399-3642
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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