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Updated: Jun 27, 2026
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Visualizing Visual Adaptation
Published on: April 24, 2017
cis-Cambios regulatorios en la expresión del ligando Kit y la evolución paralela de la pigmentación en la ballena y
Craig T Miller1, Sandra Beleza, Alex A Pollen
1HHMI and Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Cell
|December 18, 2007
Resumen
Los cambios genéticos en el ligando del gen Kit (Kitlg) impulsan la evolución paralela de la pigmentación en peces y humanos. Las variaciones reguladoras en Kitlg contribuyen a la rápida adaptación en el color de la piel de los vertebrados.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Genética La genética.
- La genómica comparada es una genómica comparada.
Sus antecedentes:
- La variación de la pigmentación está muy extendida entre las especies de vertebrados, incluidos los peces y los humanos.
- Comprender la base genética de la evolución paralela en la pigmentación es crucial para los estudios evolutivos.
Objetivo del estudio:
- Investigar los mecanismos genéticos subyacentes a la evolución paralela de los cambios de pigmentación en las poblaciones naturales de la ballena pegajosa.
- Para explorar el papel del gen ligando Kit (Kitlg) en la diversidad de pigmentación de los vertebrados.
Principales métodos:
- Utilizado cruces genéticos en sticklebacks para el mapeo de alta resolución.
- Realizó experimentos de expresión para analizar la regulación génica.
- Realizó un mapeo de mezclas en poblaciones humanas.
Principales resultados:
- Se identificó un alelo regulador divergente de Kitlg asociado con las branquias ligeras y los ventrículos de las ballenas.
- Se demostró que este alelo reduce la expresión de Kitlg en tejidos específicos.
- Encontraron alelos derivados compartidos en el locus KITLG en poblaciones humanas (europeos y asiáticos orientales) y lo vincularon con la variación del color de la piel.
Conclusiones:
- Los cambios reguladores en el gen Kitlg son un motor significativo de la variación natural en la pigmentación de los vertebrados.
- Mecanismos genéticos similares que involucran a Kitlg probablemente subyacen a los rápidos cambios evolutivos en la pigmentación en diversos grupos de vertebrados, incluidos los peces y los humanos.
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