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Molecular diversification in spider venoms: A web of combinatorial peptide libraries

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Summary

Spider venoms are a rich source of novel pharmacologically and agrochemically interesting compounds that have received increased attention from pharmacologists and biochemists in recent years. The application of technologies derived from genomics and proteomics have led to the discovery of the enormous molecular diversity of those venoms, which consist mainly of peptides and proteins. The molecular diversity of spider peptides has been revealed by mass spectrometry and appears to be based on a limited set of structural scaffolds. Genetic analysis has led to a further understanding of the molecular evolution mechanisms presiding over the generation of these combinatorial peptide libraries. Gene duplication and focal hypermutation, which has been described in cone snails, appear to be common mechanisms to venomous mollusks and spiders. Post-translational modifications, fine structural variations and new molecular scaffolds are other potential mechanisms of toxin diversification, leading to the pharmacologically complex cocktails used for predation and defense.

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Abbreviations

HPLC:

High-Performance Liquid Chromatography

MALDI-TOF MS:

Matrix-Assisted Laser desorption/ionization Time-Of-Flight Mass Spectrometry

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  1. Institut de Pharmacologie Moléculaire et Cellulaire (IPMC) – CNRS UMR 6097, 660 Route des Lucioles, Valbonne, 06560, France

    Pierre Escoubas

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Escoubas, P. Molecular diversification in spider venoms: A web of combinatorial peptide libraries. Mol Divers 10, 545–554 (2006). https://doi.org/10.1007/s11030-006-9050-4

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