Evolution of defence cocktails: Antimicrobial peptide combinations reduce mortality and persistent infection.
Mol Ecol
; 26(19): 5334-5343, 2017 Oct.
Article
en En
| MEDLINE
| ID: mdl-28762573
The simultaneous expression of costly immune effectors such as multiple antimicrobial peptides is a hallmark of innate immunity of multicellular organisms, yet the adaptive advantage remains unresolved. Here, we test current hypotheses on the evolution of such defence cocktails. We use RNAi gene knock-down to explore, the effects of three highly expressed antimicrobial peptides, displaying different degrees of activity in vitro against Staphylococcus aureus, during an infection in the beetle Tenebrio molitor. We find that a defensin confers no survival benefit but reduces bacterial loads. A coleoptericin contributes to host survival without affecting bacterial loads. An attacin has no individual effect. Simultaneous knock-down of the defensin with the other AMPs results in increased mortality and elevated bacterial loads. Contrary to common expectations, the effects on host survival and bacterial load can be independent. The expression of multiple AMPs increases host survival and contributes to the control of persisting infections and tolerance. This is an emerging property that explains the adaptive benefit of defence cocktails.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Infecciones Estafilocócicas
/
Tenebrio
/
Proteínas de Insectos
/
Inmunidad Innata
Límite:
Animals
Idioma:
En
Revista:
Mol Ecol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
SAUDE AMBIENTAL
Año:
2017
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Reino Unido