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Un transportador de piruvato dependiente de sodio y plastidial.
Tsuyoshi Furumoto1, Teppei Yamaguchi, Yumiko Ohshima-Ichie
1Graduate School of Science, Hiroshima University, 1-3-1, Kagamiyama, Higashi-Hiroshima, 739-8526, Japan. tfurumoto@hiroshima-u.ac.jp
Nature
|August 26, 2011
Resumen
Los investigadores identificaron BASS2, un nuevo transportador acoplado al sodio crucial para la importación de piruvato en los plástidos. Este descubrimiento aclara un paso clave en el metabolismo de las plantas y las vías de biosíntesis.
Área de la Ciencia:
- Biología Vegetal Biología Vegetal Biología Vegetal
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- El piruvato es un precursor vital para las vías de biosíntesis de plástidos, incluidos los ácidos grasos y los aminoácidos.
- Los mecanismos moleculares de la absorción de piruvato en los plástidos permanecen en gran medida sin caracterizar debido a los desafíos de difusión pasiva.
Objetivo del estudio:
- Identificar el mecanismo molecular responsable del transporte del piruvato en los plástidos.
- Caracterizar la función y localización de un nuevo transportador implicado en la absorción del piruvato.
Principales métodos:
- Análisis diferencial del transcriptoma de las plantas C3 y C4 (Flaveria y Cleome).
- Identificación de genes (BASS2) y estudios de localización de proteínas.
- Pruebas de expresión y transporte de proteínas recombinantes en E. coli.
- Análisis de las mutaciones de la Arabidopsis thaliana.
Principales resultados:
- Identificó BASS2 (BILE ACID:SODIUM SYMPORTER FAMILY PROTEIN 2) como un nuevo gen muy abundante en las plantas C4.
- BASS2 está localizado en la envoltura del cloroplasto y exhibe actividad de absorción de piruvato dependiente del sodio.
- Los mutantes de Arabidopsis bass2 muestran una disminución de la absorción de piruvato, afectando la síntesis de isopentenil difosfato y aumentando la sensibilidad a la mevastatina.
Conclusiones:
- BASS2 es un transportador acoplado al sodio que media la importación de piruvato en los plástidos.
- Este hallazgo proporciona evidencia molecular de un transportador de metabolito crucial en las envolturas de plástido.
- Los extendidos ortólogos BASS2 sugieren la importancia conservada de la importación de piruvato acoplado al sodio en las plantas terrestres.
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