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Evolución de los circuitos reguladores de la transcripción en las bacterias
J Christian Perez1, Eduardo A Groisman
1Department of Molecular Microbiology, Howard Hughes Medical Institute, Washington University School of Medicine, Campus Box 8230, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
Cell
|July 28, 2009
Resumen
Los organismos relacionados usan factores de transcripción similares para controlar la expresión génica, pero a menudo regulan diferentes conjuntos de genes. La evolución reguladora bacteriana involucra factores de transcripción ancestrales, transferencia de genes y cambios en los promotores, lo que lleva a una regulación genética distinta.
Área de la Ciencia:
- La genómica comparada es una genómica comparada.
- Evolución molecular de la evolución molecular.
- Regulación genética La regulación genética.
Sus antecedentes:
- Los organismos a menudo usan factores de transcripción ortólogos para responder a las señales ambientales.
- Paradójicamente, estos factores conservados con frecuencia regulan conjuntos distintos de genes en todas las especies.
- Comprender los mecanismos que impulsan estas diferencias regulatorias es crucial para la biología evolutiva.
Objetivo del estudio:
- Investigar los mecanismos subyacentes a la regulación génica divergente en organismos relacionados, centrándose particularmente en las bacterias.
- Diferenciar las funciones de la reconexión de promotores frente a los genes específicos de la especie en la divergencia reguladora.
- Explorar el impacto de la transferencia horizontal de genes en la evolución del circuito regulador bacteriano.
Principales métodos:
- Análisis comparativo de la actividad del factor de transcripción y los genes diana en especies relacionadas.
- Examen de las estructuras promotoras de genes compartidos y específicos de la especie.
- In silico y enfoques experimentales para evaluar el papel de la transferencia horizontal de genes.
Principales resultados:
- En los eucariotas, el recableado de promotores de genes compartidos es el principal impulsor de la divergencia reguladora.
- En las bacterias, los factores de transcripción ancestrales a menudo controlan los genes específicos de la especie, lo que contribuye a la novedad reguladora.
- La transferencia horizontal de genes moldea significativamente la evolución del circuito regulador bacteriano.
Conclusiones:
- La divergencia reguladora surge de mecanismos distintos en eucariotas y bacterias.
- La evolución reguladora bacteriana se caracteriza por la interacción de factores ancestrales, la transferencia horizontal de genes y las modificaciones de los promotores.
- Estos procesos evolutivos conducen a la regulación génica específica de la especie a pesar del uso de proteínas reguladoras conservadas.
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