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Venomics Reveals a Non-Compartmentalised Venom Gland in the Early Diverged Vermivorous Conus distans.

ABSTRACT: The defensive use of cone snail venom is hypothesised to have first arisen in ancestral worm-hunting snails and later repurposed in a compartmentalised venom duct to facilitate the dietary shift to molluscivory and piscivory. Consistent with its placement in a basal lineage, we demonstrate that the C. distans venom gland lacked distinct compartmentalisation. Transcriptomics revealed C. distans expressed a wide range of structural classes, with inhibitory cysteine knot (ICK)-containing peptides dominating. To better understand the evolution of the venom gland compartmentalisation, we compared C. distans to C. planorbis, the earliest diverging species from which a defence-evoked venom has been obtained, and fish-hunting C. geographus from the Gastridium subgenus that injects distinct defensive and predatory venoms. These comparisons support the hypothesis that venom gland compartmentalisation arose in worm-hunting species and enabled repurposing of venom peptides to facilitate the dietary shift from vermivory to molluscivory and piscivory in more recently diverged cone snail lineages.

SUBMITTER: Prashanth JR

PROVIDER: S-EPMC8949452 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Venomics Reveals a Non-Compartmentalised Venom Gland in the Early Diverged Vermivorous Conus distans.

Prashanth Jutty Rajan JR Dutertre Sebastien S Rai Subash Kumar SK Lewis Richard J RJ

Toxins 20220319 3

The defensive use of cone snail venom is hypothesised to have first arisen in ancestral worm-hunting snails and later repurposed in a compartmentalised venom duct to facilitate the dietary shift to molluscivory and piscivory. Consistent with its placement in a basal lineage, we demonstrate that the C. distans venom gland lacked distinct compartmentalisation. Transcriptomics revealed C. distans expressed a wide range of structural classes, with inhibitory cysteine knot (ICK)-contain ...[more]

PMID: 35324723

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Dataset Information

Venomics Reveals a Non-Compartmentalised Venom Gland in the Early Diverged Vermivorous Conus distans.

Publications

Venomics Reveals a Non-Compartmentalised Venom Gland in the Early Diverged Vermivorous <i>Conus distans</i>.

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