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Norrin / Frizzled4 señalización en el desarrollo vascular de la retina y la plasticidad de la barrera
Yanshu Wang1, Amir Rattner, Yulian Zhou
1Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Cell
|December 11, 2012
Resumen
La señalización de Norrin/Frizzled4 (Fz4) es crucial para el desarrollo vascular de la retina. La señalización defectuosa de Fz4 en las células endoteliales conduce a defectos vasculares y eliminación, destacando un mecanismo de control de calidad y funciones de función de barrera en curso.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- Biología Vascular Biología Vascular
- La neurociencia es la neurociencia.
Sus antecedentes:
- La señalización de Norrin/Frizzled4 (Fz4) activa la vía Wnt, jugando un papel clave en el desarrollo vascular de la retina.
- Las funciones precisas de la señalización de Norrin / Fz4 en las células endoteliales y las estructuras vasculares maduras siguen siendo objeto de investigación.
Objetivo del estudio:
- Investigar el papel de la señalización Norrin/Fz4 en el desarrollo y mantenimiento vascular de la retina.
- Explorar los efectos celulares autónomos y no autónomos de la señalización Fz4 en las células endoteliales.
- Para determinar el impacto de la señalización Norrin/Fz4 en la función de la barrera hemato-retiniana y hemato-encefálica.
Principales métodos:
- Se utilizaron modelos de ratones modificados genéticamente para estudiar la señalización Norrin/Fz4.
- Creó mosaicos genéticos para analizar las interacciones y el comportamiento de las células endoteliales (CE).
- Se evaluó la arquitectura vascular retiniana y la integridad de la barrera hematoencefálica/retiniana.
Principales resultados:
- La producción precoz de Norrin causó una invasión vascular retiniana prematura; el retraso en la producción condujo a defectos arquitectónicos.
- Las EC de tipo salvaje instruyeron a las EC vecinas Fz4(-/-) a formar una vasculatura normal (efecto no autónomo).
- Fz4(-/-) ECs fueron eliminados selectivamente de la vasculatura de mosaico, lo que indica un mecanismo de control de calidad.
- La señalización alterada de Norrin/Fz4 en ratones adultos afectó la función de la barrera hemato-retiniana y hemato-encefálica, mostrando plasticidad.
Conclusiones:
- La señalización Norrin/Fz4 es esencial para el desarrollo vascular normal de la retina y la supervivencia de las células endoteliales.
- Un sistema de control de calidad vascular elimina las células endoteliales defectuosas con deficiencia de Fz4.
- La señalización frizzled es vital para mantener las barreras sangre-retina y sangre-cerebro y exhibe plasticidad en la vasculatura madura del SNC.
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