Convergent evolution of pain-inducing defensive venom components in spitting cobras.
Science
; 371(6527): 386-390, 2021 01 22.
Article
in En
| MEDLINE
| ID: mdl-33479150
ABSTRACT
Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A2 (PLA2) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pain
/
Sensory Receptor Cells
/
Elapidae
/
Evolution, Molecular
/
Elapid Venoms
/
Group IV Phospholipases A2
Limits:
Animals
Language:
En
Journal:
Science
Year:
2021
Document type:
Article
Affiliation country: