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Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
Published on: March 22, 2016
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Un conjunto supramolecular media la integración del ADN lentiviral
Allison Ballandras-Colas1, Daniel P Maskell1, Erik Serrao2,3
1Chromatin Structure and Mobile DNA, The Francis Crick Institute, London, NW1 1AT, UK.
Science (New York, N.Y.)
|January 7, 2017
Resumen
Los investigadores visualizaron el maedi-visna lentivirus en el microsoma utilizando la criomicroscopia electrónica. Esta estructura revela cómo la integrasa retroviral (IN) forma complejos para la inserción de ADN, ayudando al diseño del inhibidor del VIH- 1.
Área de la Ciencia:
- Biología estructural
- Virología
- Biología molecular
Sus antecedentes:
- La integrasa retroviral (IN) es esencial para la integración del ADN viral en la cromatina del huésped.
- El intasoma es el complejo funcional de nucleoproteínas donde la IN cataliza la inserción del ADN viral.
- Comprender la estructura del intasoma es clave para inhibir la replicación retroviral.
Objetivo del estudio:
- Para visualizar la estructura funcional del maedi-visna en el lentivirus en alta resolución.
- Aclarar la arquitectura del complejo IN y su mecanismo catalítico.
- Proporcionar información para el desarrollo de nuevas terapias antivirales.
Principales métodos:
- Se empleó la criomicroscopia electrónica (crio-EM) para determinar la estructura del intasoma.
- Las imágenes de alta resolución (4,9 angstroms) permitieron una visualización detallada del complejo.
- El análisis estructural se centró en el conjunto homo-hexadecámero de IN.
Principales resultados:
- El maedi-visna lentivirus en el intasoma exhibe una arquitectura tetrámica de tetrámeros, una homo-hexadecámara de IN.
- Se identificaron ocho tipos distintos de protómeros de IN, que apoyan dos subunidades catalíticamente activas.
- Un núcleo intasomal conservado está formado por dos tetrámeros IN, con dominios C-terminales que completan la interfaz sináptica.
Conclusiones:
- El estudio explica cómo el VIH-1 IN forma intasomas funcionales a través de la multimerización de orden superior.
- Estos hallazgos concilian los datos bioquímicos y estructurales previos sobre el VIH-1 IN.
- La estructura del intasoma lentiviral proporciona una plataforma para el diseño de inhibidores dirigidos del VIH-1.
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