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Title: Atlas of the neuromuscular system in the Trachymedusa Aglantha digitale : Insights from the advanced hydrozoan
Abstract

Cnidaria is the sister taxon to bilaterian animals, and therefore, represents a key reference lineage to understand early origins and evolution of the neural systems. The hydromedusaAglantha digitaleis arguably the best electrophysiologically studied jellyfish because of its system of giant axons and unique fast swimming/escape behaviors. Here, using a combination of scanning electron microscopy and immunohistochemistry together with phalloidin labeling, we systematically characterize both neural and muscular systems inAglantha, summarizing and expanding further the previous knowledge on the microscopic neuroanatomy of this crucial reference species. We found that the majority, if not all (~2,500) neurons, that are labeled by FMRFamide antibody are different from those revealed by anti‐α‐tubulin immunostaining, making these two neuronal markers complementary to each other and, therefore, expanding the diversity of neural elements inAglanthawith two distinct neural subsystems. Our data uncovered the complex organization of neural networks forming a functional “annulus‐type” central nervous system with three subsets of giant axons, dozen subtypes of neurons, muscles, and a variety of receptors fully integrated with epithelial conductive pathways supporting swimming, escape and feeding behaviors. The observed unique adaptations within theAglanthalineage (including giant axons innervating striated muscles) strongly support an extensive and wide‐spread parallel evolution of integrative and effector systems across Metazoa.

 
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Award ID(s):
1645219 1548121
NSF-PAR ID:
10457665
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Comparative Neurology
Volume:
528
Issue:
7
ISSN:
0021-9967
Page Range / eLocation ID:
p. 1231-1254
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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