Caveolin-3 directly interacts with the C-terminal tail of beta -dystroglycan. Identification of a central WW-like domain within caveolin family members

J Biol Chem. 2000 Dec 1;275(48):38048-58. doi: 10.1074/jbc.M005321200.

Abstract

Caveolin-3, the most recently recognized member of the caveolin gene family, is muscle-specific and is found in both cardiac and skeletal muscle, as well as smooth muscle cells. Several independent lines of evidence indicate that caveolin-3 is localized to the sarcolemma, where it associates with the dystrophin-glycoprotein complex. However, it remains unknown which component of the dystrophin complex interacts with caveolin-3. Here, we demonstrate that caveolin-3 directly interacts with beta-dystroglycan, an integral membrane component of the dystrophin complex. Our results indicate that caveolin-3 co-localizes, co-fractionates, and co-immunoprecipitates with a fusion protein containing the cytoplasmic tail of beta-dystroglycan. In addition, we show that a novel WW-like domain within caveolin-3 directly recognizes the extreme C terminus of beta-dystroglycan that contains a PPXY motif. As the WW domain of dystrophin recognizes the same site within beta-dystroglycan, we also demonstrate that caveolin-3 can effectively block the interaction of dystrophin with beta-dystroglycan. In this regard, interaction of caveolin-3 with beta-dystroglycan may competitively regulate the recruitment of dystrophin to the sarcolemma. We discuss the possible implications of our findings in the context of Duchenne muscular dystrophy.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3T3 Cells
  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Caveolin 3
  • Caveolins / chemistry
  • Caveolins / metabolism*
  • Cytoskeletal Proteins / chemistry
  • Cytoskeletal Proteins / metabolism*
  • Dystroglycans
  • Membrane Glycoproteins / chemistry
  • Membrane Glycoproteins / metabolism*
  • Mice
  • Molecular Sequence Data
  • Precipitin Tests
  • Protein Binding
  • Sequence Homology, Amino Acid

Substances

  • Cav3 protein, mouse
  • Caveolin 3
  • Caveolins
  • Cytoskeletal Proteins
  • Membrane Glycoproteins
  • Dystroglycans

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