Integrin-linked kinase stabilizes myotendinous junctions and protects muscle from stress-induced damage.
J Cell Biol
; 180(5): 1037-49, 2008 Mar 10.
Article
en En
| MEDLINE
| ID: mdl-18332223
ABSTRACT
Skeletal muscle expresses high levels of integrin-linked kinase (ILK), predominantly at myotendinous junctions (MTJs) and costameres. ILK binds the cytoplasmic domain of beta1 integrin and mediates phosphorylation of protein kinase B (PKB)/Akt, which in turn plays a central role during skeletal muscle regeneration. We show that mice with a skeletal muscle-restricted deletion of ILK develop a mild progressive muscular dystrophy mainly restricted to the MTJs with detachment of basement membranes and accumulation of extracellular matrix. Endurance exercise training enhances the defects at MTJs, leads to disturbed subsarcolemmal myofiber architecture, and abrogates phosphorylation of Ser473 as well as phosphorylation of Thr308 of PKB/Akt. The reduction in PKB/Akt activation is accompanied by an impaired insulin-like growth factor 1 receptor (IGF-1R) activation. Coimmunoprecipitation experiments reveal that the beta1 integrin subunit is associated with the IGF-1R in muscle cells. Our data identify the beta1 integrin-ILK complex as an important component of IGF-1R/insulin receptor substrate signaling to PKB/Akt during mechanical stress in skeletal muscle.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Tendones
/
Proteínas Serina-Treonina Quinasas
/
Músculo Esquelético
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Fibras Musculares Esqueléticas
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Integrina beta1
/
Distrofia Muscular Animal
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Cell Biol
Año:
2008
Tipo del documento:
Article
País de afiliación:
Alemania