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Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds
Published on: June 7, 2013
TOPLESS regula el destino embrionario apical en la especie Arabidopsis
Jeff A Long1, Carolyn Ohno, Zachery R Smith
1Plant Biology Laboratory, Salk Institute for Biological Sciences, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA. long@salk.edu
Science (New York, N.Y.)
|June 10, 2006
Resumen
La mutación topless-1 (tpl-1) en Arabidopsis redirige el desarrollo del polo de brote hacia un segundo polo de raíz. Esto sugiere que un mecanismo de represión transcripcional evita la formación de raíces en el ápice del brote durante la embriogénesis.
Área de la Ciencia:
- Biología del desarrollo vegetal Biología del desarrollo vegetal
- Genética molecular genética molecular.
- La investigación de la Arabidopsis thaliana también está en marcha.
Sus antecedentes:
- Los embriones de las plantas desarrollan distintos brotes apicales y polos de raíces basales.
- La mutación topless-1 (tpl-1) en Arabidopsis interrumpe esta polaridad, creando un segundo polo de raíz en el ápice del brote.
Objetivo del estudio:
- Para dilucidar el mecanismo molecular subyacente a la regulación mediada por TPL del desarrollo del poste de disparo en la embriogénesis de Arabidopsis.
- Investigar el papel de los corepresores y coactivadores de la transcripción en el establecimiento de la polaridad apical-basal de las plantas.
Principales métodos:
- Análisis genético del mutante topless-1 (tpl-1) de la especie Arabidopsis.
- Caracterización de la función de la proteína TPL y su interacción con otras proteínas reguladoras.
- Investigando los efectos de las mutaciones en los genes de la histona acetiltransferasa y la desacetilasa en el fenotipo tpl-1.
Principales resultados:
- La proteína TPL funciona como un corepresor de la transcripción.
- La mutación tpl-1 actúa de manera dominante-negativa, afectando a múltiples proteínas relacionadas con la TPL.
- Las mutaciones en HISTONE ACETYLTRANSFERASE GNAT SUPERFAMILY1 suprimen el fenotipo tpl-1, mientras que las mutaciones en HISTONE DEACETYLASE19 lo mejoran y causan defectos apicales similares.
Conclusiones:
- Un mecanismo de represión transcripcional es esencial para prevenir la formación de raíces en el poste de brote durante la embriogénesis de Arabidopsis.
- La TPL y las enzimas modificadoras de histonas asociadas juegan un papel crítico en el establecimiento y mantenimiento de la polaridad embrionaria en las plantas.
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