%0 Journal Article %A Sandhya Singh %A Aakash Gaur %A Renu Kumari %A Shakti Prakash %A Sunaina Kumari %A Ayushi Devendrasingh Chaudhary %A Rakesh Kumar Sharma %A Pankaj Prasun %A Priyanka Pant %A Thomas Thum %A Kumaravelu Jagavelu %A Pragya Bharati %A Kashif Hanif %A Pragya Chitkara %A Shailesh Kumar %A Kalyan Mitra %A Shashi Kumar Gupta %T Musashi-2 causes cardiac hypertrophy and heart failure by inducing mitochondrial dysfunction through destabilizing Cluh and Smyd1 mRNA %D 2023 %R 10.1101/2023.03.01.530580 %J bioRxiv %P 2023.03.01.530580 %X Regulation of RNA stability and translation by RNA-binding proteins (RBPs) is a crucial process altering gene expression. Musashi family of RBPs comprising Msi1 and Msi2 are known to control RNA stability and translation. However, despite the presence of MSI2 in the heart, its function remains entirely unknown. Here, we aim to explore the cardiac functions of MSI2. We confirmed the presence of MSI2 in the adult mouse, rat heart, and neonatal rat cardiomyocytes. Furthermore, Msi2 was significantly enriched in the heart’s cardiomyocyte fraction. Next, using RNA-seq data and isoform-specific PCR primers, we identified, Msi2 isoforms 1, 4, and 5 and two novel putative isoforms labeled as Msi2 isoforms 6 and 7 to be expressed in the heart. Overexpression of Msi2 isoforms led to cardiac hypertrophy in cultured cardiomyocytes. Additionally, Msi2 was also found to be significantly increased in a pressure-overload model of cardiac hypertrophy. To validate the hypertrophic effects, we selected isoforms 4 and 7 due to their unique alternative splicing patterns. AAV9-mediated overexpression of Msi2 isoforms 4 and 7 in murine hearts led to cardiac hypertrophy, dilation, heart failure, and eventually early death, confirming a pathological function for Msi2. Using global proteomics, gene ontology, transmission electron microscopy, and transmembrane potential measurement assays increased MSI2 was found to cause mitochondrial dysfunction in the heart. Mechanistically, we identified Cluh and Smyd1 as direct downstream targets of Msi2. Overexpression of Cluh or Smyd1 inhibited Msi2-induced hypertrophy and mitochondrial dysfunction in cardiomyocytes. Collectively, we show that Msi2 induces hypertrophy, mitochondrial dysfunction, and heart failure.Competing Interest StatementThe authors have declared no competing interest.RBPRNA-binding proteinAAVAdeno-associated virusGFPGreen fluorescent proteinUTRUntranslated regionDNADeoxyribonucleic acidRNARibonucleic acidrRNARibosomal RNAtRNATransfer RNAmRNAmessenger RNANCBINational Center for Biotechnology InformationPCRPolymerase chain reactionDAPI4’,6-diamidino-2-phenylindoleTEMTransmission Electron MicroscopeRRMRNA recognition motifsLC-MS/MSLiquid Chromatography with tandem mass spectrometryGOGene OntologyTCATricarboxylic AcidAREAdenylate-uridylate-rich elementsTMRETetramethylrhodamine, ethyl esterTACTrans-aortic constrictionFPKMFragment per kilobase of transcript per million read pairsMOIMultiplicity of Infection %U https://www.biorxiv.org/content/biorxiv/early/2023/03/02/2023.03.01.530580.full.pdf