Skip to content
Open access

Biallelic titin truncation disrupts sarcomere assembly and function in patient-derived iPSC-cardiomyocytes.

Aug 2026 · Journal of Molecular and Cellular Cardiology · Vol 218, pp. 130-136 · 0 citations · 15 references
Medicine

TL;DR

Using induced pluripotent stem cell-derived cardiomyocytes from a biallelic TTNtv patient with dilated cardiomyopathy, sarcomere structure/function is investigated and inefficient sarcomere assembly and interaction promotes cardiomyopathy in biallelic TTNtv.

Abstract

Biallelic titin truncation variants (TTNtvs) are linked to severe cardiac and skeletal muscle diseases, due to unclear mechanisms. Using induced pluripotent stem cell-derived cardiomyocytes from a biallelic TTNtv patient with dilated cardiomyopathy, we investigated sarcomere structure/function. Only the longest of the TTNtvs was detected as protein, and this nearly full-length titin was incorporated into the sarcomere. Subtle structural alterations occurred, with shortened A-bands observed in a subset of sarcomeres. Resulting reduction and imbalance of force development was linked to lowered contractility, and many sarcomeres being stretched by their neighbors. Thus, inefficient sarcomere assembly and interaction promotes cardiomyopathy in biallelic TTNtv.

Read PDF

Similar papers

Review Open access Sep 2026

Emerging Roles of Dystroglycan in Cardiac Remodeling, Fibrosis, and Heart Failure

The dystrophin–glycoprotein complex (DGC) is a structural and signaling network of cardiac muscle. It connects the extracellular matrix to the intracellular cytoskeleton. Dystroglycan, a component of the DGC, plays an essential role in maintaining the integrity of the sarcolemma of cardiac muscle. It contributes to sar...

B. S. Pradhan, M. Mączewski · 0 citations
Open access Aug 2026

Desmoplakin Loss Leads to PKC- and Src-Mediated Contractile Dysfunction in Cardiomyocytes

Background Mutations in DSP, which encodes the protein desmoplakin, lead to cardiomyopathy with unusually high penetrance that presents with arrhythmias, fibro-fatty infiltration, and eventually heart failure. However, the precise mechanism of contractile dysfunction and dilation are incompletely understood. Here, we i...

Ilhan Gokhan, Maggie McKay, Xia Li et al. · 0 citations
Aug 2026

Loss of bves leads to cardiac contractile dysfunction and myocardial mitochondrial damage in zebrafish.

The Popeye domain-containing protein 1 (Popdc1, also known as Bves) is a transmembrane protein whose dysfunction is closely associated with various diseases. Clinical studies have identified that mutations in the bves gene predispose individuals to limb-girdle muscular dystrophy. However, a marked reduction in Bves pro...

Wanwan Cai, Wan-Bang Zhou, Jun-Rong Lei et al. · 0 citations
#gene editing Review Open access Aug 2026

Assembly and Maintenance of Myofibrils in the Heart.

This review will discuss the general principles of myofibril assembly in the heart and cover new findings on myofibril maintenance and turnover.

Elisabeth Ehler · 0 citations
Review Jul 2026

Rewriting the sarcomere: Gene therapy approaches for hypertrophic cardiomyopathy from bench to bedside.

Hypertrophic cardiomyopathy (HCM) is a prototypical inherited cardiomyopathy with well-defined sarcomeric genetic underpinnings that make it an attractive target for molecular therapy. We review recent advances in gene-based approaches for HCM, including adeno-associated virus-mediate gene replacement, allele-specific...

Susan K. Keen, Barry Greenberg, M. Desai · 0 citations
Open access Jul 2026

SGLT2 inhibition improves sarcomere contractile dysfunction in human models of dilated cardiomyopathy

It is found that a subcellular signaling pathway dysregulated in DCM CMs, clathrin-mediated endocytosis (CME)-dependent signaling, may be recovered by EMP treatment in DCM TPM1-L185F iPSC-CMs, which supports that EMP modulates aspects of CME-signaling, and contributes to restored sarcomere functions.

Daria Plota, H. N. Saleem, K. Lin et al. · 0 citations

We use cookies to run the site and, with your consent, for analytics and to show ads. See our Cookie Policy.