Changes in cell shape and desmin intermediate filament distribution are associated with down-regulation of desmin expression in C2C12 myoblasts grown in the absence of extracellular Ca2+
Rev. bras. pesqui. méd. biol
; Braz. j. med. biol. res;38(7)July 2005. ilus, graf
Article
en En
| LILACS
| ID: lil-403857
Biblioteca responsable:
BR1.1
ABSTRACT
Desmin is the main intermediate filament (IF) protein of muscle cells. In skeletal muscle, desmin IFs form a scaffold that interconnects the entire contractile apparatus with the subsarcolemmal cytoskeleton and cytoplasmic organelles. The interaction between desmin and the sarcolemma is mediated by a number of membrane proteins, many of which are Ca2+-sensitive. In the present study, we analyzed the effects of the Ca2+ chelator EGTA (1.75 mM) on the expression and distribution of desmin in C2C12 myoblasts grown in culture. We used indirect immunofluorescence microscopy and reverse transcription polymerase chain reaction (RT-PCR) to analyze desmin distribution and expression in C2C12 cells grown in the presence or absence of EGTA. Control C2C12 myoblasts showed a well-spread morphology after a few hours in culture and became bipolar when grown for 24 h in the presence of EGTA. Control C2C12 cells showed a dense network of desmin from the perinuclear region to the cell periphery, whereas EGTA-treated cells showed desmin aggregates in the cytoplasm. RT-PCR analysis revealed a down-regulation of desmin expression in EGTA-treated C2C12 cells compared to untreated cells. The present results suggest that extracellular Ca2+ availability plays a role in the regulation of desmin expression and in the spatial distribution of desmin IFs in myoblasts, and is involved in the generation and maintenance of myoblast cell shape.
Texto completo:
1
Colección:
01-internacional
Base de datos:
LILACS
Asunto principal:
Filamentos Intermedios
/
Calcio
/
Músculo Esquelético
/
Mioblastos
/
Forma de la Célula
/
Desmina
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
Idioma:
En
Revista:
Braz. j. med. biol. res
/
Rev. bras. pesqui. méd. biol
Asunto de la revista:
BIOLOGIA
/
MEDICINA
Año:
2005
Tipo del documento:
Article
/
Congress and conference
País de afiliación:
Brasil
Pais de publicación:
Brasil