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Comparative analyses of glycerotoxin expression unveil a novel structural organization of the bloodworm venom system.

ABSTRACT: We present the first molecular characterization of glycerotoxin (GLTx), a potent neurotoxin found in the venom of the bloodworm Glycera tridactyla (Glyceridae, Annelida). Within the animal kingdom, GLTx shows a unique mode of action as it can specifically up-regulate the activity of Cav2.2 channels (N-type) in a reversible manner. The lack of sequence information has so far hampered a detailed understanding of its mode of action.Our analyses reveal three ~3.8 kb GLTx full-length transcripts, show that GLTx represents a multigene family, and suggest it functions as a dimer. An integrative approach using transcriptomics, quantitative real-time PCR, in situ hybridization, and immunocytochemistry shows that GLTx is highly expressed exclusively in four pharyngeal lobes, a previously unrecognized part of the venom apparatus.Our results overturn a century old textbook view on the glycerid venom system, suggesting that it is anatomically and functionally much more complex than previously thought. The herein presented GLTx sequence information constitutes an important step towards the establishment of GLTx as a versatile tool to understand the mechanism of synaptic function, as well as the mode of action of this novel neurotoxin.

SUBMITTER: Richter S

PROVIDER: S-EPMC5336659 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Comparative analyses of glycerotoxin expression unveil a novel structural organization of the bloodworm venom system.

Richter Sandy S Helm Conrad C Meunier Frederic A FA Hering Lars L Campbell Lahcen I LI Drukewitz Stephan H SH Undheim Eivind A B EA Jenner Ronald A RA Schiavo Giampietro G Bleidorn Christoph C

BMC evolutionary biology 20170304 1

<h4>Background</h4>We present the first molecular characterization of glycerotoxin (GLTx), a potent neurotoxin found in the venom of the bloodworm Glycera tridactyla (Glyceridae, Annelida). Within the animal kingdom, GLTx shows a unique mode of action as it can specifically up-regulate the activity of Ca<sub>v</sub>2.2 channels (N-type) in a reversible manner. The lack of sequence information has so far hampered a detailed understanding of its mode of action.<h4>Results</h4>Our analyses reveal t ...[more]

PMID: 28259138

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Comparative analyses of glycerotoxin expression unveil a novel structural organization of the bloodworm venom system.

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Comparative analyses of glycerotoxin expression unveil a novel structural organization of the bloodworm venom system.

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