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Nε-Acilación grasa de las GTPasas Rho por un efector de la toxina MARTX
Yan Zhou1, Chunfeng Huang1, Li Yin1
1Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang 310058, China.
Science (New York, N.Y.)
|October 28, 2017
Resumen
Las toxinas bacterianas llamadas toxinas MARTX liberan dominios efectores en las células huésped. Un dominio, RID, actúa como una aciltransferasa grasa, modificando las Rho GTPasas y interrumpiendo la señalización de las células huésped.
Área de la Ciencia:
- Microbiología
- Biología molecular
- La bioquímica
Sus antecedentes:
- Las toxinas multifuncionales de autoprocesamiento repetido en la toxina (MARTX) son prevalentes en los patógenos bacterianos.
- Estas toxinas se agrupan en dominios efectores que modulan las vías de señalización del huésped.
Objetivo del estudio:
- Para investigar la función del dominio de inactivación de la GTPasa Rho (RID) de las toxinas MARTX.
- Elucidar el mecanismo por el cual la RID interrumpe el citoesqueleto de actina del huésped y causa el redondeo celular.
Principales métodos:
- Ensayos bioquímicos para determinar la actividad enzimática de la RID.
- Análisis de la modificación de la GTPasa Rho en las células huésped.
Principales resultados:
- RID funciona como una aciltransferasa Nε-grasa.
- RID modifica covalentemente los residuos de lisina en la región polibásica C-terminal de las Rho GTPasas.
- La acilación grasa de las GTPasas Rho inhibe su actividad e interrumpe la señalización aguas abajo.
Conclusiones:
- La RID media la acilación de las proteínas de los mamíferos por la lisina Nε.
- Las toxinas MARTX representan una nueva familia de toxinas bacterianas con actividad de N-grasa aciltransferasa.
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