αvß6- and αvß8-integrins serve as interchangeable receptors for HSV gH/gL to promote endocytosis and activation of membrane fusion.
PLoS Pathog
; 9(12): e1003806, 2013.
Article
en En
| MEDLINE
| ID: mdl-24367260
ABSTRACT
Herpes simplex virus (HSV)--and herpesviruses in general--encode for a multipartite entry/fusion apparatus. In HSV it consists of the HSV-specific glycoprotein D (gD), and three additional glycoproteins, gH/gL and gB, conserved across the Herpesviridae family and responsible for the execution of fusion. According to the current model, upon receptor binding, gD propagates the activation to gH/gL and to gB in a cascade fashion. Questions remain about how the cascade of activation is controlled and how it is synchronized with virion endocytosis, to avoid premature activation and exhaustion of the glycoproteins. We considered the possibility that such control might be carried out by as yet unknown receptors. Indeed, receptors for HSV gB, but not for gH/gL, have been described. In other members of the Herpesviridae family, such as Epstein-Barr virus, integrin receptors bind gH/gL and trigger conformational changes in the glycoproteins. We report that αvß6- and αvß8-integrins serve as receptors for HSV entry into experimental models of keratinocytes and other epithelial and neuronal cells. Evidence rests on loss of function experiments, in which integrins were blocked by antibodies or silenced, and gain of function experiments in which αvß6-integrin was expressed in integrin-negative cells. αvß6- and αvß8-integrins acted independently and are thus interchangeable. Both bind gH/gL with high affinity. The interaction profoundly affects the route of HSV entry and directs the virus to acidic endosomes. In the case of αvß8, but not αvß6-integrin, the portal of entry is located at lipid microdomains and requires dynamin 2. Thus, a major role of αvß6- or αvß8-integrin in HSV infection appears to be to function as gH/gL receptors and to promote virus endocytosis. We propose that placing the gH/gL activation under the integrin trigger point enables HSV to synchronize virion endocytosis with the cascade of glycoprotein activation that culminates in execution of fusion.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Receptores Virales
/
Integrinas
/
Proteínas del Envoltorio Viral
/
Simplexvirus
/
Internalización del Virus
/
Antígenos de Neoplasias
Tipo de estudio:
Prognostic_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
PLoS Pathog
Año:
2013
Tipo del documento:
Article
País de afiliación:
Italia