Myopalladin knockout mice develop cardiac dilation and show a maladaptive response to mechanical pressure overload
- Institute of Genetic and Biomedical Research (IRGB) - National Research Council (CNR), Milan unit, Italy
- IRCCS Humanitas Research Hospital, United States
- King's College London BHF Centre of Research Excellence, United Kingdom
- University of Florence, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Italy
- IRCCS Humanitas Research Hospital, Italy
- University of California San Diego, United States
- National Research Council, Italy
- University of Muenster, Germany
- King's College London, United Kingdom
Abstract
Myopalladin (MYPN) is a striated muscle-specific immunoglobulin domain-containing protein located in the sarcomeric Z-line and I-band. MYPN gene mutations are causative for dilated (DCM), hypertrophic and restrictive cardiomyopathy. In a yeast two-hybrid screening, MYPN was found to bind to titin in the Z-line, which was confirmed by microscale thermophoresis. Cardiac analyses of MYPN knockout (MKO) mice showed the development of mild cardiac dilation and systolic dysfunction, associated with decreased myofibrillar isometric tension generation and increased resting tension at longer sarcomere lengths. MKO mice exhibited a normal hypertrophic response to transaortic constriction (TAC), but rapidly developed severe cardiac dilation and systolic dysfunction, associated with fibrosis, increased fetal gene expression, higher intercalated disc fold amplitude, decreased calsequestrin-2 protein levels, and increased desmoplakin and SORBS2 protein levels. Cardiomyocyte analyses showed delayed Ca2+ release and reuptake in unstressed MKO mice as well as reduced Ca2+ spark amplitude post-TAC, suggesting that altered Ca2+ handling may contribute to the development of DCM in MKO mice.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures.
Article and author information
Author details
Funding
Fondazione Telethon (GGP12282)
- Marie-Louise Bang
Ministero dell'Istruzione, dell'Università e della Ricerca (2010R8JK2X_006)
- Marie-Louise Bang
Ministero della Salute (RF-MUL-2007-666195)
- Marie-Louise Bang
Fondazione Cariplo (2007.5812)
- Marie-Louise Bang
Agenzia Spaziale Italiana (2015-009-R.0)
- Marie-Louise Bang
European Commission (777204)
- Corrado Poggesi
Wellcome Trust (201543/Z/16)
- Mathias Gautel
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal studies were approved by the Italian Ministry of Health and performed in full compliance with the rules and regulations of the European Union (Directive 2010/63/EU of the European Parliament) and Italy (Council of 22 September 2010; directive from the Italian Ministry of Health) on the protection of animals use for scientific purposes.
Copyright
© 2021, Filomena et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 991
- views
-
- 162
- downloads
-
- 15
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Myopalladin knockout mice develop cardiac dilation and show a maladaptive response to mechanical pressure overload
eLife 10:e58313.
https://doi.org/10.7554/eLife.58313
Further reading
-
- Biochemistry and Chemical Biology
- Stem Cells and Regenerative Medicine
Human induced pluripotent stem cells (hiPSCs) have great potential to be used as alternatives to embryonic stem cells (hESCs) in regenerative medicine and disease modelling. In this study, we characterise the proteomes of multiple hiPSC and hESC lines derived from independent donors and find that while they express a near-identical set of proteins, they show consistent quantitative differences in the abundance of a subset of proteins. hiPSCs have increased total protein content, while maintaining a comparable cell cycle profile to hESCs, with increased abundance of cytoplasmic and mitochondrial proteins required to sustain high growth rates, including nutrient transporters and metabolic proteins. Prominent changes detected in proteins involved in mitochondrial metabolism correlated with enhanced mitochondrial potential, shown using high-resolution respirometry. hiPSCs also produced higher levels of secreted proteins, including growth factors and proteins involved in the inhibition of the immune system. The data indicate that reprogramming of fibroblasts to hiPSCs produces important differences in cytoplasmic and mitochondrial proteins compared to hESCs, with consequences affecting growth and metabolism. This study improves our understanding of the molecular differences between hiPSCs and hESCs, with implications for potential risks and benefits for their use in future disease modelling and therapeutic applications.
-
- Biochemistry and Chemical Biology
- Structural Biology and Molecular Biophysics
Dynamic conformational and structural changes in proteins and protein complexes play a central and ubiquitous role in the regulation of protein function, yet it is very challenging to study these changes, especially for large protein complexes, under physiological conditions. Here, we introduce a novel isobaric crosslinker, Qlinker, for studying conformational and structural changes in proteins and protein complexes using quantitative crosslinking mass spectrometry. Qlinkers are small and simple, amine-reactive molecules with an optimal extended distance of ~10 Å, which use MS2 reporter ions for relative quantification of Qlinker-modified peptides derived from different samples. We synthesized the 2-plex Q2linker and showed that the Q2linker can provide quantitative crosslinking data that pinpoints key conformational and structural changes in biosensors, binary and ternary complexes composed of the general transcription factors TBP, TFIIA, and TFIIB, and RNA polymerase II complexes.
