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El gen de la triosefosfato isomerasa del maíz: los intrones son anteriores a la divergencia animal-vegetal
Cell
|July 4, 1986
Resumen
Se analizaron las intrones del gen de la raíz de maíz triosefosfato isomerasa (TPI). Las posiciones de intrones sugieren que existían antes de la divergencia animal-vegetal, con animales que perdieron dos intrones.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La triosefosfato isomerasa (TPI) es una enzima crucial en la glucólisis.
- Comprender la estructura genética, incluidos los intrones, proporciona información sobre la historia evolutiva.
Objetivo del estudio:
- Para clonar y caracterizar el gen de la raíz de maíz triosefosfato isomerasa (TPI).
- Para comparar la estructura intrón-exón del gen TPI del maíz con la de otras especies, particularmente animales, para inferir relaciones evolutivas.
Principales métodos:
- clonación y caracterización de ADN cDNA y ADN genómico.
- Análisis de secuencias y comparación de los límites intrón-exón.
- Análisis filogenético de la estructura genética.
Principales resultados:
- El gen TPI de la raíz de maíz fue clonado y caracterizado con éxito.
- El gen contiene ocho intrones.
- La comparación con el TPI de pollo reveló posiciones de intrones conservadas, un intrón desplazado e intrones nuevos, lo que indica una homología estructural significativa.
Conclusiones:
- El alto grado de conservación de la posición del intrón sugiere que los intrones estaban presentes en el gen ancestral antes de la divergencia de las plantas y los animales.
- El gen ancestral probablemente poseía al menos ocho intrones.
- El linaje animal parece haber perdido dos intrones durante la evolución.
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