Impact of ANKRD1 mutations associated with hypertrophic cardiomyopathy on contraction parameters of engineered heart tissue

Basic Res Cardiol. 2013 May;108(3):349. doi: 10.1007/s00395-013-0349-x. Epub 2013 Apr 10.

Abstract

Hypertrophic cardiomyopathy (HCM) is a myocardial disease associated with mutations in sarcomeric genes. Three mutations were found in ANKRD1, encoding ankyrin repeat domain 1 (ANKRD1), a transcriptional co-factor located in the sarcomere. In the present study, we investigated whether expression of HCM-associated ANKRD1 mutations affects contraction parameters after gene transfer in engineered heart tissues (EHTs). EHTs were generated from neonatal rat heart cells and were transduced with adeno-associated virus encoding GFP or myc-tagged wild-type (WT) or mutant (P52A, T123M, or I280V) ANKRD1. Contraction parameters were analyzed from day 8 to day 16 of culture, and evaluated in the absence or presence of the proteasome inhibitor epoxomicin for 24 h. Under standard conditions, only WT- and T123M-ANKRD1 were correctly incorporated in the sarcomere. T123M-ANKRD1-transduced EHTs exhibited higher force and velocities of contraction and relaxation than WT- P52A- and I280V-ANKRD1 were highly unstable, not incorporated into the sarcomere, and did not induce contractile alterations. After epoxomicin treatment, P52A and I280V were both stabilized and incorporated into the sarcomere. I280V-transduced EHTs showed prolonged relaxation. These data suggest different impacts of ANKRD1 mutations on cardiomyocyte function: gain-of-function for T123M mutation under all conditions and dominant-negative effect for the I280V mutation which may come into play only when the proteasome is impaired.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Cardiomyopathy, Hypertrophic / genetics*
  • Cardiomyopathy, Hypertrophic / metabolism
  • Cardiomyopathy, Hypertrophic / physiopathology
  • Cells, Cultured
  • Dependovirus / genetics
  • Fluorescent Antibody Technique
  • Gene Expression Regulation
  • Genetic Vectors
  • Genotype
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Humans
  • Muscle Proteins / genetics*
  • Muscle Proteins / metabolism
  • Mutation*
  • Myocardial Contraction / drug effects
  • Myocardial Contraction / genetics*
  • Myocytes, Cardiac / drug effects
  • Myocytes, Cardiac / metabolism*
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Oligopeptides / pharmacology
  • Phenotype
  • Proteasome Endopeptidase Complex / metabolism
  • Proteasome Inhibitors / pharmacology
  • Rats
  • Repressor Proteins / genetics*
  • Repressor Proteins / metabolism
  • Time Factors
  • Tissue Engineering* / methods
  • Transduction, Genetic
  • Transfection

Substances

  • ANKRD1 protein, human
  • Muscle Proteins
  • Nuclear Proteins
  • Oligopeptides
  • Proteasome Inhibitors
  • Repressor Proteins
  • Green Fluorescent Proteins
  • Proteasome Endopeptidase Complex
  • epoxomicin