Perturbation of the titin/MURF1 signaling complex is associated with hypertrophic cardiomyopathy in a fish model and in human patients. Academic Article uri icon

Overview

abstract

  • Hypertrophic cardiomyopathy (HCM) is a hereditary disease characterized by cardiac hypertrophy with diastolic dysfunction. Gene mutations causing HCM have been found in about half of HCM patients, while the genetic etiology and pathogenesis remain unknown for many cases of HCM. To identify novel mechanisms underlying HCM pathogenesis, we generated a cardiovascular-mutant medaka fish, non-spring heart (nsh), which showed diastolic dysfunction and hypertrophic myocardium. The nsh homozygotes had fewer myofibrils, disrupted sarcomeres and expressed pathologically stiffer titin isoforms. In addition, the nsh heterozygotes showed M-line disassembly that is similar to the pathological changes found in HCM. Positional cloning revealed a missense mutation in an immunoglobulin (Ig) domain located in the M-line-A-band transition zone of titin. Screening of mutations in 96 unrelated patients with familial HCM, who had no previously implicated mutations in known sarcomeric gene candidates, identified two mutations in Ig domains close to the M-line region of titin. In vitro studies revealed that the mutations found both in medaka fish and in familial HCM increased binding of titin to muscle-specific ring finger protein 1 (MURF1) and enhanced titin degradation by ubiquitination. These findings implicate an impaired interaction between titin and MURF1 as a novel mechanism underlying the pathogenesis of HCM.

authors

  • Higashikuse, Yuta
  • Mittal, Nishant
  • Arimura, Takuro
  • Yoon, Sung Han
  • Oda, Mayumi
  • Enomoto, Hirokazu
  • Kaneda, Ruri
  • Hattori, Fumiyuki
  • Suzuki, Takeshi
  • Kawakami, Atsushi
  • Gasch, Alexander
  • Furukawa, Tetsushi
  • Labeit, Siegfried
  • Fukuda, Keiichi
  • Kimura, Akinori
  • Makino, Shinji

publication date

  • November 15, 2019

Research

keywords

  • Cardiomyopathy, Hypertrophic
  • Connectin
  • Disease Models, Animal
  • Muscle Proteins
  • Mutation
  • Tripartite Motif Proteins
  • Ubiquitin-Protein Ligases

Identity

PubMed Central ID

  • PMC6899042

Scopus Document Identifier

  • 85075813412

Digital Object Identifier (DOI)

  • 10.1038/ng816

PubMed ID

  • 31628103

Additional Document Info

volume

  • 12

issue

  • 11