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La fosforilación dependiente del factor de crecimiento epidérmico de la lipocortina
Nature
|May 1, 1986
Resumen
La lipocortina, una proteína antiinflamatoria, es fosforilada por la quinasa del receptor del factor de crecimiento epidérmico (EGF). Esta fosforilación ocurre cerca de la proteína.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
Sus antecedentes:
- Las proteínas similares a la lipocortina son inhibidores de la fosfolipasa inducidos por esteroides con potencial antiinflamatorio.
- Estas proteínas se encuentran en varios tejidos y especies.
- La lipocortina de 40.000 K de peso molecular es fosforilada por las proteínas cinasas, lo que sugiere que la fosforilación regula su actividad.
Objetivo del estudio:
- Para investigar la fosforilación de la lipocortina humana por la quinasa del receptor del factor de crecimiento epidérmico (EGF).
- Para determinar si la lipocortina es el sustrato endógeno para el receptor/cinasa del EGF en las células A431.
Principales métodos:
- El mapeo de péptidos se utilizó para analizar el sitio de fosforilación en la lipocortina humana.
- Se realizaron análisis inmunológicos para comparar la lipocortina con el sustrato receptor/cinasa del FEA.
- Los experimentos se llevaron a cabo utilizando la línea celular A431.
Principales resultados:
- La lipocortina humana es fosforilada cerca de su extremo amino por el receptor/cinasa EGF.
- El mapeo de péptidos y los datos inmunológicos confirman que la lipocortina es idéntica al sustrato endógeno 35K fosforilado por el receptor/cinasa EGF en las células A431.
Conclusiones:
- El receptor/cinasa del FEA fosforila directamente la lipocortina humana.
- La lipocortina es el sustrato 35K endógeno para el receptor/cinasa del EGF en las células A431, vinculando la señalización del EGF a la regulación de la lipocortina.
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