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Regulación de la estructura de Golgi a través de las proteínas G heterotriméricas
C Jamora1, P A Takizawa, R F Zaarour
1Department of Biology, University of California San Diego, La Jolla 92093-0347, USA.
Cell
|December 11, 1997
Resumen
El metabolito de las esponjas marinas, la ilimaquinona (IQ), causa la vesiculación de Golgi independientemente del ARF y los coatómicos. Este proceso implica la activación de la proteína G heterotrimérica, con subunidades libres de betagamma que desencadenan la vesiculación de la pila de Golgi.
Área de la Ciencia:
- Productos naturales del mar productos naturales del mar.
- Biología celular Biología celular.
- La señalización molecular.
Sus antecedentes:
- Se sabe que la ilimaquinona (IQ), un metabolito de la esponja marina, induce la vesiculación completa de las pilas de Golgi.
- El mecanismo preciso de la vesiculación de Golgi mediada por el CI y su relación con las vías conocidas de formación de vesículas sigue sin estar claro.
Objetivo del estudio:
- Para dilucidar el mecanismo molecular subyacente a la vesiculación de Golgi inducida por la ilimaquinona (IQ).
- Para determinar si la vesiculación de Golgi mediada por el CI requiere componentes de la vía de formación de vesículas COPI, como ARF y coatómeros.
Principales métodos:
- Reconstitución de la vesiculación de Golgi mediada por el CI en células permeabilizadas.
- Investigación del papel de la ARF, los coátomos y las proteínas G heterotriméricas en el proceso de vesiculación.
- Evaluación de los efectos inhibidores de G alpha (((s) -GDP y G alpha (((i3) -GDP, y el efecto de las subunidades betagamma.
Principales resultados:
- La vesiculación de Golgi mediada por el CI se produce independientemente de la ARF y los coátomos, factores clave en la formación de vesículas COPI.
- El proceso es inhibido por G alpha(s) -GDP y G alpha(i3) -GDP, lo que sugiere la participación de las proteínas G heterotriméricas.
- La adición de subunidades betagamma por sí sola, sin IQ, es suficiente para inducir la vesiculación de la pila de Golgi.
Conclusiones:
- La vesiculación de Golgi inducida por el CI está mediada por la activación de las proteínas G heterotriméricas.
- La especie activa que desencadena la vesiculación de Golgi es la subunidad betagamma libre, no la subunidad alfa activada.
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