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Quantitative PCR-based Assay to Measure Sonic Hedgehog Signaling in Cellular Model of Ciliogenesis
Published on: January 31, 2025
El receptor ciliar acoplado a la proteína G Gpr161 regula negativamente la vía Sonic hedgehog a través de la
Saikat Mukhopadhyay1, Xiaohui Wen, Navneet Ratti
1Department of Research Oncology, Genentech Inc., South San Francisco, CA 94080, USA. saikat.mukhopadhyay@utsouthwestern.edu
Cell
|January 22, 2013
Resumen
El receptor acoplado a la proteína G Gpr161 es crucial para la regulación de la señalización Sonic hedgehog (Shh) en los cilios primarios. Su pérdida aumenta la señalización Shh, lo que afecta el desarrollo del tubo neural.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología del desarrollo Biología del desarrollo.
- Biología Molecular Biología Molecular
Sus antecedentes:
- El cilium primario es esencial para la señalización Sonic hedgehog (Shh) en los vertebrados.
- Las mutaciones en el complejo de transporte intraflagelar A (IFT-A) paradójicamente aumentan la señalización Shh.
- El IFT-A recluta a la proteína similar a un tubo, Tulp3, hacia los cilios.
Objetivo del estudio:
- Identificar nuevos componentes involucrados en la regulación de la señalización Shh dentro de los cilios primarios.
- Investigar el papel de Gpr161 en la localización ciliar dependiente de Tulp3/IFT-A y la modulación de la vía Shh.
Principales métodos:
- Se utilizaron modelos de ratón con pérdida genética de Gpr161.1.
- Se analizó la localización de los cilios primarios de Gpr161 en relación con Tulp3 e IFT-A.
- Se evaluó la actividad de la vía de señalización Shh y el procesamiento de Gli3 en mutantes Gpr161.
- Se midieron los niveles de AMP cíclico (cAMP) y la internalización de Gpr161 desde los cilios.
Principales resultados:
- Gpr161 se localiza en los cilios primarios de una manera dependiente de Tulp3/IFT-A.
- La pérdida completa de Gpr161 en ratones conduce a la letalidad a mitad de la gestación y a una elevación de la señalización Shh del tubo neural, imitando a los mutantes Tulp3/IFT-A.
- El Gpr161 activo eleva la cAMP, reprimiendo la señalización Shh mediante la promoción de la forma represora de Gli3.
- La señalización Shh induce la internalización de Gpr161 desde los cilios, inhibiendo su actividad.
Conclusiones:
- Gpr161 es un regulador clave de la señalización Shh en los cilios primarios.
- Gpr161 funciona como un receptor acoplado a la proteína G de vertebrados conservado esencial para el desarrollo del tubo neural.
- Gpr161 define una vía que une la activación de la proteína quinasa A a la señalización Shh a través de la modulación cAMP y el procesamiento Gli3.
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