Functional and structural diversification of the Anguimorpha lizard venom system

Area of Science:

• * Evolutionary biology
• * Molecular biology
• * Biochemistry

Background:

• * Venom in Anguimorpha lizards is a recently discovered basal trait.
• * Limited knowledge exists on toxin evolution, recruitment timing, and venom system diversification in these lizards.

Purpose of the Study:

• * To investigate the evolutionary history of venom in the Anguimorpha clade.
• * To identify novel venom components and understand their molecular evolution.
• * To analyze the diversification of venom gland morphology.

Main Methods:

• * Multidisciplinary approach across the Anguimorpha taxonomic range.
• * Analysis of cDNA libraries for venom transcriptomes.
• * Phylogenetic analyses and venom gland morphology examination.

Main Results:

• * Discovery of three new cardioactive peptide toxins: celestoxin, cholecystokinin, and YY peptides.
• * Identification of novel venom gland-overexpressed proteins (epididymal secretory protein, ribonuclease).
• * Sequencing of lectin, hyaluronidase, and veficolin toxins, showing homology to snake venom forms.
• * Phylogenetic evidence for independent recruitment of natriuretic peptide toxins compared to snakes.
• * De novo evolution of helokinestatin peptide toxin domains in helodermatid/anguid subclade.
• * Identification of new isoforms for cysteine-rich secretory protein, kallikrein, and phospholipase A(2).
• * Morphological analysis revealed independent evolution of specialized serous protein-secreting glands in distinct lineages.

Conclusions:

• * Lizard venom systems exhibit complex transcriptomes and significant evolutionary innovation.
• * Convergent evolution is evident in the recruitment of genes for venom components.
• * The findings underscore the potential of lizard venoms for biodiscovery and drug development.