Myofibril diameter is set by a finely tuned mechanism of protein oligomerization in Drosophila.
Elife
; 82019 11 20.
Article
en En
| MEDLINE
| ID: mdl-31746737
Myofibrils are huge cytoskeletal assemblies embedded in the cytosol of muscle cells. They consist of arrays of sarcomeres, the smallest contractile unit of muscles. Within a muscle type, myofibril diameter is highly invariant and contributes to its physiological properties, yet little is known about the underlying mechanisms setting myofibril diameter. Here we show that the PDZ and LIM domain protein Zasp, a structural component of Z-discs, mediates Z-disc and thereby myofibril growth through protein oligomerization. Oligomerization is induced by an interaction of its ZM domain with LIM domains. Oligomerization is terminated upon upregulation of shorter Zasp isoforms which lack LIM domains at later developmental stages. The balance between these two isoforms, which we call growing and blocking isoforms sets the stereotyped diameter of myofibrils. If blocking isoforms dominate, myofibrils become smaller. If growing isoforms dominate, myofibrils and Z-discs enlarge, eventually resulting in large pathological aggregates that disrupt muscle function.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Portadoras
/
Proteínas de Drosophila
/
Drosophila
/
Multimerización de Proteína
/
Miofibrillas
Límite:
Animals
Idioma:
En
Revista:
Elife
Año:
2019
Tipo del documento:
Article
País de afiliación:
Canadá
Pais de publicación:
Reino Unido