FBXO32, encoding a member of the SCF complex, is mutated in dilated cardiomyopathy

Genome Biol. 2016 Jan 11;17:2. doi: 10.1186/s13059-015-0861-4.

Abstract

Background: Dilated cardiomyopathy (DCM) is a common form of cardiomyopathy causing systolic dysfunction and heart failure. Rare variants in more than 30 genes, mostly encoding sarcomeric proteins and proteins of the cytoskeleton, have been implicated in familial DCM to date. Yet, the majority of variants causing DCM remain to be identified. The goal of the study is to identify novel mutations causing familial dilated cardiomyopathy.

Results: We identify FBXO32 (ATROGIN 1), a member of the F-Box protein family, as a novel DCM-causing locus. The missense mutation affects a highly conserved amino acid and is predicted to severely impair binding to SCF proteins. This is validated by co-immunoprecipitation experiments from cells expressing the mutant protein and from human heart tissue from two of the affected patients. We also demonstrate that the hearts of the patients with the FBXO32 mutation show accumulation of selected proteins regulating autophagy.

Conclusion: Our results indicate that abnormal SCF activity with subsequent impairment of the autophagic flux due to a novel FBXO32 mutation is implicated in the pathogenesis of DCM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence / genetics
  • Autophagy / genetics
  • Cardiomyopathy, Dilated / genetics*
  • Cardiomyopathy, Dilated / pathology
  • Cytoskeleton / genetics
  • Cytoskeleton / metabolism
  • Gene Expression Regulation
  • Genetic Linkage
  • Genetic Predisposition to Disease
  • Heart Failure / genetics*
  • Heart Failure / pathology
  • Humans
  • Muscle Proteins / genetics*
  • Muscle Proteins / metabolism
  • Mutation, Missense / genetics
  • SKP Cullin F-Box Protein Ligases / genetics*
  • SKP Cullin F-Box Protein Ligases / metabolism
  • Sarcomeres / genetics
  • Sarcomeres / metabolism

Substances

  • Muscle Proteins
  • FBXO32 protein, human
  • SKP Cullin F-Box Protein Ligases