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Fluorescence Activated Cell Sorting of Plant Protoplasts
Published on: February 18, 2010
Identificación y función de la adenilil ciclasa en la señalización de la auxina en las plantas superiores
T Ichikawa1, Y Suzuki, I Czaja
1Max Planck Institut für Züchtungsforschung, Köln, Germany.
Nature
|December 31, 1997
Resumen
La AMP cíclica (cAMP) juega un papel en la división celular superior de las plantas. Los investigadores identificaron una nueva planta de adenilil ciclasa, que demuestra el cAMP.
Área de la Ciencia:
- Biología Molecular Vegetal Biología Molecular Vegetal
- La señalización celular de las células.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La AMP cíclica (cAMP) es una molécula de señalización crucial en procariotas y eucariotas.
- Su papel en plantas más altas ha sido históricamente dudoso debido a la baja actividad de la adenilil ciclasa y los niveles de cAMP.
- La fitohormona auxina es esencial para la división celular de las plantas.
Objetivo del estudio:
- Para investigar el papel de la cAMP en la división celular superior de las plantas.
- Para identificar y caracterizar la adenilil ciclasa en las plantas superiores.
Principales métodos:
- Se utilizó el etiquetado de ADN-T de activación para generar líneas celulares de tabaco.
- Se aisló un ADN complementario (ADNc) que codifica la adenilil ciclasa de una línea marcada.
- El ADNc aislado fue expresado en *Escherichia coli* y levadura (*Schizosaccharomyces pombe*).
- Los protoplastos del tabaco fueron tratados con cAMP, forskolina o dideoxyadenosina.
Principales resultados:
- Se aisló un nuevo ADNc de adenilil ciclasa del tabaco, mostrando similitud con el de la levadura adenilil ciclasa.
- La expresión de la adenilil ciclasa del tabaco en *E. coli* aumentó los niveles de cAMP.
- La expresión en la levadura complementó una mutación en la levadura.
- El tratamiento con cAMP o forskolina permitió la división de los protoplastos del tabaco sin auxina.
- El inhibidor de la adenilil ciclasa, la dideoxyadenosina, bloqueaba la proliferación celular inducida por la auxina.
Conclusiones:
- La AMP cíclica está involucrada en la división celular desencadenada por la auxina en las plantas superiores.
- Se ha identificado una adenilil ciclasa funcional en una planta superior.
- Este estudio proporciona evidencia de un papel significativo de la señalización cAMP en el desarrollo de las plantas.
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