Exp Mol Med.  2003 Dec;35(6):538-544.

Dysferlin in a hyperCKaemic patient with caveolin 3 mutation and in C2C12 cells after p38 MAP kinase inhibition

• Capanni C
• Sabatelli
• Mattioli E
• Ognibene A
• Columbaro
• Lattanzi G
• Merlini L
• Minetti C
• Maraldi NM
• Squarzoni

Abstract

Dysferlin is a plasma membrane protein of skeletal muscle whose deficiency causes Miyoshi myopathy, limb girdle muscular dystrophy 2B and distal anterior compartment myopathy. Recent studies have reported that dysferlin is implicated in membrane repair mechanism and coimmunoprecipitates with caveolin 3 in human skeletal muscle. Caveolin 3 is a principal structural protein of caveolae membrane domains in striated muscle cells and cardiac myocytes. Mutations of caveolin 3 gene (CAV3) cause different diseases and where caveolin 3 expression is defective, dysferlin localization is abnormal. We describe the alteration of dysferlin expression and localization in skeletal muscle from a patient with raised serum creatine kinase (hyperCKaemia), whose reduction of caveolin 3 is caused by a CAV3 P28L mutation. Moreover, we performed a study on dysferlin interaction with caveolin 3 in C2C12 cells. We show the association of dysferlin to cellular membrane of C2C12 myotubes and the low affinity link between dysferlin and caveolin 3 by immunoprecipitation techniques. We also reproduced caveolinopathy conditions in C2C12 cells by a selective p38 MAP kinase inhibition with SB203580, which blocks the expression of caveolin 3. In this model, myoblasts do not fuse into myotubes and we found that dysferlin expression is reduced. These results underline the importance of dysferlin-caveolin 3 relationship for skeletal muscle integrity and propose a cellular model to clarify the dysferlin alteration mechanisms in caveolinopathies.

Keyword

caveolin; C2C12; dysferlin; membranes fusion; muscular dystrophy; p38 MAP kinase

MeSH Terms

Animals
Biopsy
Caveolin 3
Caveolins/*genetics/metabolism
Cell Line
Creatine Kinase/*blood
Enzyme Inhibitors/*pharmacology
Humans
Imidazoles/pharmacology
Insulin/pharmacology
Membrane Proteins/*metabolism
Mice
Mitogen-Activated Protein Kinases/*antagonists & inhibitors/metabolism
Muscle Proteins/*metabolism
Muscle, Skeletal/cytology/metabolism
Mutation/*genetics
Protein Binding
Pyridines/pharmacology
p38 Mitogen-Activated Protein Kinases