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Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog
Published on: November 5, 2014
Una familia conservada de prolyl-4-hidroxilasas que modifican el HIF
1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard L3.124, Dallas, TX 75390-9152, USA.
Science (New York, N.Y.)
|October 13, 2001
Resumen
Las enzimas HIF prolyl hidroxilasa (HPH) son cruciales para detectar los niveles de oxígeno en las células. Estas enzimas se dirigen al factor inducible a la hipoxia (HIF) para la degradación, evitando su acumulación en condiciones normales de oxígeno.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
Sus antecedentes:
- Las células de mamíferos utilizan una vía conservada regulada por el factor inducible a la hipoxia (HIF) para responder a los cambios de oxígeno.
- La subunidad alfa HIF se degrada bajo normoxia a través de un complejo ubiquitina-ligasa que reconoce un residuo de prolina hidroxilado.
Objetivo del estudio:
- Para identificar las enzimas responsables de la hidroxilación del HIF.
- Para investigar el papel de estas enzimas en la detección de oxígeno.
Principales métodos:
- Identificación de una familia conservada de enzimas de la HIF prolyl hidroxilasa (HPH).
- Coexpresión de HPH en células de mamíferos para observar los efectos en la acumulación de HIF.
- Interferencia de ARN en las células de Drosophila melanogaster para suprimir la HPH y evaluar la expresión génica.
Principales resultados:
- Se identificaron enzimas HPH como responsables de la hidroxilación de la prolina HIF.
- Coexpresión de la acumulación de HIF-1alfa atenuada de HPH bajo normoxia en células de mamíferos.
- La supresión de HPH en las células de Drosophila condujo a un aumento de la expresión génica de la lactato deshidrogenasa (LDH) bajo normoxia.
Conclusiones:
- Las enzimas HPH son componentes esenciales de la vía celular de detección de oxígeno.
- HPH juega un papel crítico en la regulación de la estabilidad de HIF y la expresión génica aguas abajo en respuesta a los niveles de oxígeno.
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