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Cambios morfológicos inducidos por el éster de forbol en los fibroblastos transformados de pollo: evidencia de
Cell
|May 1, 1979
Resumen
Phorbol myristate acetate (PMA) desencadena la producción de activador de plasminógeno (PA) de la serina proteasa en las células, causando cambios morfológicos. Los inhibidores específicos de la proteasa bloquean estos cambios, identificando a la PA como la enzima clave responsable.
Área de la Ciencia:
- Biología celular Biología celular.
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
Sus antecedentes:
- El Phorbol myristate acetate (PMA) es un conocido promotor de tumores.
- La PMA induce la producción de activador de plasminógeno (PA), una serina proteasa, en las células cultivadas.
- La producción de PA se mejora en los fibroblastos embrionarios de pollo transformados por el virus del sarcoma de Rous (RSVCEF).
Objetivo del estudio:
- Investigar el papel de la PA en los cambios morfológicos inducidos por la PMA en RSVCEF.
- Para identificar la proteasa serina específica responsable de estas alteraciones celulares.
- Para determinar si la PA puede alterar el comportamiento celular independientemente del plasminogén.
Principales métodos:
- Tratamiento de cultivos de RSVCEF con PMA.
- Análisis de la actividad de PA utilizando un sustrato fluorescente.
- Estudios de inhibición con el uso de varios inhibidores de la proteasa (leupeptina, NPGB, SBTI, benzamidina, DFP).
- Etiquetado de las enzimas serinas en el fluido de cultivo con 3H-DFP.
Principales resultados:
- El tratamiento con PMA indujo cambios morfológicos significativos en el RSVCEF, incluido el agrupamiento celular.
- Estos cambios morfológicos fueron inhibidos por los inhibidores de la enzima serina, particularmente DFP.
- La inhibición de la actividad de la AP se correlacionó directamente con la inhibición de las alteraciones morfológicas.
- El etiquetado 3H-DFP confirmó la PA como la serina proteasa responsable de los cambios observados.
Conclusiones:
- El activador de plasminógeno (PA) es la serina proteasa que media los cambios morfológicos inducidos por PMA en RSVCEF.
- La PA puede alterar catalíticamente el comportamiento celular independientemente de su sustrato natural, el plasminógeno.
- Estos hallazgos resaltan el papel de la PA en la modulación de la morfología y el comportamiento celular.
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