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La proteína disulfuro isomerasa como regulador de la activación traslacional de los cloroplastos
1Department of Cell Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Science (New York, N.Y.)
|January 7, 1998
Resumen
La expresión génica regulada por la luz en los cloroplastos está controlada por un nuevo mecanismo. Una isomerasa disulfuro de proteína modula las proteínas de unión al poliadenilato de los cloroplastos.
Área de la Ciencia:
- Biología Vegetal Biología Vegetal Biología Vegetal
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
Sus antecedentes:
- La traducción regulada por la luz de los ARN mensajeros de los cloroplastos (ARNm) depende de los factores que se unen a la región 5' no traducida (UTR).
- La proteína de unión al poliadenilato de los cloroplastos (cPABP) es crucial para la traducción del ARNm psbA a través de la unión 5'-UTR.
Objetivo del estudio:
- Investigar el mecanismo que regula la unión de la cPABP al ARNm psbA 5'-UTR.
- Para identificar los factores que modulan la interacción de la cPABP con el ARNm.
Principales métodos:
- Co-purificación de las proteínas de los cloroplastos con cPABP.
- Análisis de la actividad de la proteína disulfuro isomerasa en la unión de la cPABP.
- Investigando los efectos de redox y fosforilación en la interacción cPABP-mRNA.
Principales resultados:
- Se identificó una isomerasa disulfuro de proteína localizada en los cloroplastos.
- Esta enzima modula la unión de la cPABP con el mRNA psbA 5'-UTR.
- Los cambios reversibles en el estado redox de la cPABP regulan su unión.
Conclusiones:
- Un nuevo interruptor sensible al redox controla la expresión génica del cloroplasto.
- La actividad de la proteína disulfuro isomerasa proporciona un mecanismo reversible para regular la iniciación de la traducción.
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