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Una nueva integrina del receptor de vitronectina (alfa v beta x) es responsable de las distintas propiedades
D A Cheresh1, J W Smith, H M Cooper
1Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Cell
|April 7, 1989
Resumen
Las células de carcinoma utilizan un receptor de integrina único para la adhesión de vitronectina y fibronectina, distinto del receptor de vitronectina que se encuentra en las células de melanoma y endotelio. Esta nueva integrina comprende una subunidad alfa v y una nueva subunidad beta x, destacando diversas funciones de la integrina en las interacciones de la matriz celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las integrinas son receptores cruciales de la superficie celular que median las interacciones célula-matriz.
- Los diferentes tipos de células exhiben perfiles de expresión de integrina distintos, lo que influye en la adhesión.
- Se sabe que el receptor de vitronectina (alfa v beta 3) se une a múltiples proteínas matriciales.
Objetivo del estudio:
- Caracterizar la nueva integrina involucrada en la adhesión celular del carcinoma.
- Para determinar la composición de la subunidad de la integrina de la célula del carcinoma.
- Para aclarar el papel funcional de esta integrina en el reconocimiento de matrices.
Principales métodos:
- Los ensayos de adhesión celular utilizan vitronectina, fibrinógeno y el factor de von Willebrand.
- Experimentos de bloqueo de anticuerpos dirigidos a subunidades de integrina.
- Análisis de la mancha del norte para detectar ARNm de la subunidad de integrina específica.
Principales resultados:
- Las células de carcinoma se adhieren a la vitronectina a través de una nueva integrina, a diferencia del melanoma y las células endoteliales que expresan alfa v beta 3.
- La integrina del carcinoma comparte la subunidad alfa v, pero posee una subunidad beta x distinta.
- Esta nueva integrina media la adhesión tanto a la vitronectina como a la fibronectina.
Conclusiones:
- Las células de carcinoma emplean una integrina única (alfa v beta x) para la adhesión matriz específica.
- Las subunidades alfa homólogas pueden emparejarse con subunidades beta distintas para crear integrinas funcionalmente diversas.
- La estructura de las integrinas dicta el reconocimiento diferencial de los componentes de la matriz extracelular.
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