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La pinopsina es una molécula fotorreceptiva pineal de pollo
T Okano1, T Yoshizawa, Y Fukada
1Department of Pure and Applied Sciences, College of Arts and Sciences, University of Tokyo, Japan.
Nature
|November 3, 1994
Resumen
Los investigadores identificaron una nueva molécula sensible a la luz, la pinopsina, en los pinealocitos de pollo. Este descubrimiento arroja luz sobre los mecanismos moleculares del reloj biológico aviar y la producción de melatonina.
Área de la Ciencia:
- * Biología Molecular.
- * Cronobiología.
- * Visión Ciencia de la visión.
Sus antecedentes:
- * Los pinealocitos aviares regulan los ritmos circadianos y la producción de melatonina a través de señales de luz.
- * La vía de fototransducción pineal es crucial para entender el reloj biológico.
- * Existen similitudes entre las células varillas de la retina y los pinealocitos en la fototransducción.
Objetivo del estudio:
- * Para identificar la molécula fotorreceptiva en los pinealocitos aviares.
- * Para aclarar el mecanismo molecular del reloj biológico aviar.
- * Para caracterizar el fotorreceptor pineal clonado.
Principales métodos:
- * Clonado de cDNA pineal de pollo que codifica una molécula fotorreceptiva.
- * Transfección de ADN complementario en células de cultivo.
- * Reconstitución de la proteína expresada con 11-cis-retinal.
Principales resultados:
- * Una nueva opsin, llamada pinopsin, fue clonada a partir del cDNA pineal de pollo.
- * La opsina pineal del pollo comparte un 43-48% de identidad de aminoácidos con las opsinas de la retina de los vertebrados.
- * La pinopsina expresada reconstituida con 11-cis-retinal formó un pigmento sensible al azul (λmax ≈ 470 nm).
- * El gen que codifica la pinopsina se expresa específicamente en la glándula pineal.
Conclusiones:
- * La pinopsina funciona como el fotosensor primario en la glándula pineal de las aves.
- * Este hallazgo revela un componente molecular clave del reloj circadiano de las aves.
- * El estudio proporciona evidencia funcional para el papel de la pinopsina en la fototransducción.
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