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Una regla basada en la zona media ajusta la compactación cromosómica a la longitud del eje de la anafase.
Gabriel Neurohr1, Andreas Naegeli, Iris Titos
1Centre for Genomic Regulation (CRG), Barcelona, Spain.
Science (New York, N.Y.)
|March 12, 2011
Resumen
Las células de levadura adaptan la condensación cromosómica a la longitud del huso durante la mitosis. Esto asegura una segregación cromatídica adecuada, incluso con el aumento de las dimensiones del cromosoma o del huso.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- Genética La genética.
Sus antecedentes:
- La segregación de las cromatidas mitóticas depende de la condensación coordinada de los cromosomas y de la longitud del husillo.
- La relación entre la condensación cromosómica y el alargamiento del huso sigue sin estar clara.
Objetivo del estudio:
- Para investigar si la condensación cromosómica y el alargamiento del huso están vinculados durante la mitosis.
- Comprender los mecanismos que utilizan las células para adaptarse a las variaciones en el tamaño del cromosoma y del huso.
Principales métodos:
- Utilizó la levadura como organismo modelo.
- Se manipuló la longitud del brazo cromosómico y se observaron respuestas celulares.
- Se analizaron los roles de la zona media del husillo, la aurora / Ipl1 quinasa y la fosforilación de la histona H3 (Ser10) en este proceso.
Principales resultados:
- Las células de levadura compensaron con éxito un aumento del 45% en la longitud del brazo cromosómico más largo al mejorar su condensación.
- La zona media del husillo, la actividad de la aurora / Ipl1 y la fosforilación de la histona H3 Ser10 se identificaron como mediadores clave de esta respuesta de condensación adaptativa.
Conclusiones:
- El husillo anafásico puede actuar como una regla, detectando y adaptando los niveles de condensación cromatídica.
- Este mecanismo de adaptación mediado por el huso promueve una robusta segregación cromatídica a través de diferentes longitudes de cromosomas y huso.
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