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A Fluorogenic Peptide Cleavage Assay to Screen for Proteolytic Activity: Applications for coronavirus spike protein activation
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Los coronavirus explotan una proteasa cisteína-aspártica huésped para la replicación
Hin Chu1,2,3,4, Yuxin Hou5, Dong Yang5
1State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, China. hinchu@hku.hk.
Nature
|August 3, 2022
Resumen
Los coronavirus explotan la vía de la apoptosis del huésped mediante el uso de la caspasa-6 para dividir las proteínas virales. Este proceso genera fragmentos que bloquean la respuesta inmune, mejorando la replicación del virus y la patogénesis.
Área de la Ciencia:
- Virología
- Biología molecular
- Inmunología
Sus antecedentes:
- Los coronavirus altamente patogénicos como el SARS-CoV-2, el MERS-CoV y el SARS-CoV-1 causan una apoptosis significativa.
- La apoptosis está relacionada con la patogénesis de estos virus respiratorios graves.
Objetivo del estudio:
- Para investigar el papel de la caspasa-6, una proteasa clave de la apoptosis, en la replicación del coronavirus.
- Para dilucidar el mecanismo por el cual los coronavirus interactúan con la cascada de apoptosis del huésped.
Principales métodos:
- Pruebas enzimáticas para demostrar la escisión de las proteínas nucleocápsidas virales por caspasa-6.
- Estudios in vivo con modelos animales (hámsters y ratones) para evaluar el efecto de la inhibición de la caspasa-6 en la infección viral y la patología.
Principales resultados:
- Caspase-6 divide las proteínas nucleocapsidas del coronavirus en fragmentos que actúan como antagonistas del interferón.
- La inhibición de la caspasa-6 redujo significativamente la patología pulmonar y la pérdida de peso en los hámsteres infectados por SARS-CoV-2.
- La inhibición de la caspasa-6 mejoró la supervivencia en ratones infectados por MERS-CoV.
Conclusiones:
- La caspasa-6 es un factor huésped crítico que facilita la replicación eficiente del coronavirus.
- Los coronavirus secuestran la maquinaria de apoptosis del huésped, específicamente la caspasa-6, para evadir las respuestas inmunes y promover la propagación viral.
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