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La transducción en las células receptoras del gusto requiere de una proteína quinasa dependiente de la cAMP
P Avenet1, F Hofmann, B Lindemann
1Physiology II, Universität des Saarlandes, Homburg, FRG.
Nature
|January 28, 1988
Resumen
El monofosfato cíclico de adenosina (cAMP) desencadena la despolarización de las células gustativas mediante la activación de una proteína quinasa. Esta quinasa inactiva canales de potasio específicos, que difieren de otras células sensoriales.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Biología celular Biología celular.
- Fisiología Sensorial Fisiología Sensorial.
Sus antecedentes:
- El monofosfato cíclico de adenosina (cAMP) es un mensajero intracelular en la quimiorrecepción del gusto.
- Las células receptoras del sabor dulce generan cAMP en respuesta a estímulos dulces.
- El mecanismo por el cual el cAMP actúa sobre las membranas celulares de los receptores gustativos no se comprende completamente.
Objetivo del estudio:
- Investigar el mecanismo por el cual la cAMP causa despolarización en las células receptoras del gusto.
- Para identificar los canales iónicos específicos y las vías de señalización involucradas en la señalización gustativa mediada por cAMP.
Principales métodos:
- Grabaciones de parches de células enteras de las células de los receptores gustativos.
- Experimentos de parche de membrana de adentro hacia afuera.
- Análisis electrofisiológico de la actividad de los canales iónicos.
Principales resultados:
- cAMP causa una despolarización significativa de las células receptoras del gusto.
- Esta despolarización está mediada por la proteína quinasa dependiente de la cAMP.
- La proteína quinasa inactiva los canales de potasio con una conductividad predominante de 44 pS.
Conclusiones:
- La señalización intracelular gustativa difiere de la señalización olfativa y fotorreceptor.
- cAMP en las células gustativas actúa a través de la fosforilación de los canales iónicos, no la unión directa.
- Este mecanismo de fosforilación regula la actividad de los canales de potasio y la excitabilidad de las células gustativas.
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