Project description:Restrictive cardiomyopathy (RCM) is a severe cardiac disorder characterized by impaired ventricular filling and diastolic dysfunction, with mutations in sarcomeric proteins representing major causative factors. Mutations of TNNI3 gene (e.g. p.R192H) constitute major genetic causes of RCM, particularly affecting pediatric patients and being associated with poor prognosis. Here, we demonstrate that adenine base editor (ABE) is able effectively correct RCM-causing mutation and alleviate RCM in a murine model. We first developed a novel murine model harboring the Tnni3R193H mutation that recapitulates the hallmark features of human RCM. Importantly, targeted delivery of ABE via adeno-associated virus (AAV) achieved efficient and precise correction of the Tnni3R193H mutation in adult RCM mice, leading to significant improvement of cardiac functions. Our findings establish base editing as a therapeutic strategy for RCM and highlight its broader potential for treating genetic cardiomyopathies in clinical settings.
Project description:To investigate the physiological characteristics of cardiomyocytes (CM) in restrictive cardiomyopathy (RCM), we established RCM(heterozygous)-iPSC and produced RCM(homozygous)-iPSC and corrected Isogenic-iPSC using CRISPER-CAS9 technology. Then, we used the RNA-seq data obtained from these three iPSCs and three different healthy iPSC-derived CMs for gene expression profiling analysis.
Project description:An amino acid exchange (P209L) in the HSPB8 binding site of the human cochaperone Bcl2-associated athanogene 3 (BAG3) gives rise to severe dominant childhood cardiomyopathy. To phenocopy the human disease in mouse and gain insight into its mechanisms, we have generated humanized transgenic mouse models. Expression of human BAG3P209L-eGFP in mice caused Z-disc disintegration and formation of protein aggregates. This was accompanied by massive fibrosis resulting in a severe, early-onset restrictive cardiomyopathy with increased mortality, as observed in patients. RNA-Seq and proteomic analysis revealed changes in the protein quality control system and increased autophagy in hearts from hBAG3P209L-eGFP overexpressing mice. Also, the mutation renders hBAG3P209L less soluble in vivo and induces protein aggregation, but does not abrogate hBAG3 binding properties. Thus, we have established a mouse model recapitulating mimicing the human disease and found that the disease mechanism is due to accumulation of hBAG3P209L and mouse BAG3, causing sequestering of components of the protein quality control system and the autophagy machinery leading to the reduction of the stability and functional organization of sarcomeres. We have also tested a gene therapy approach utilizing expression of shRNA against hBAG3 in cardiac muscle via AAV and demonstrate that this halted and even partially reversed major phenotypic features of the disease.
Project description:We used NGS of rna to understand transcriptome wide changes that occur in the left ventricles of pediatric idiopathic dilated cardiomyopathy patients.
Project description:Genomic editing of pathogenic TNNI3 mutation in restrictive cardiomyopathy rescues diastolic dysfunction of human induced pluripotent stem cell-derived cardiomyocytes
Project description:Circular RNAs (circRNAs) have emerged as essential regulators and biomarkers of various disease. To assess differential expression levels of circRNAs in pediatric dilated cardiomyopathy (PDCM) and explore their biological and mechanistic significance.