Project description:In cardiomyocytes, Ca2+ influx through L-type voltage-gated calcium channels (LTCCs) following membrane depolarization regulates crucial Ca2+-dependent processes including duration and amplitude of the action potentials and excitation-contraction coupling. LTCCs are heteromultimeric proteins composed of the Cav1, Cav, Cav2 and Cav subunits. Here, using ascorbate peroxidase (APEX)-mediated proximity labeling and quantitative proteomics, we identified 61 proteins in the nano-environments of Cav2 in cardiomyocytes. These proteins are involved in diverse cellular functions such as cellular trafficking, muscular contraction, sarcomere organization and excitation-contraction coupling. Moreover, pull-down assays, co-immunoprecipitation analyses and super-resolution imaging using direct stochastic optical reconstruction microscopy (dSTORM) revealed that Cav2 interacts with the ryanodine receptor 2 (RyR2) in adult cardiomyocytes, probably coupling LTCCs and the RyR2 into a supramolecular complex at the dyads. This interaction is mediated by the Src-homology 3 domain of Cav2 and is necessary for an effective pacing frequency‐dependent increase of the Ca2+-induced Ca2+ release mechanism in cardiomyocytes.
Project description:Here, we characterize the transcriptome of the mouse embryonic stem cell line CM7-1 during differentiation into beating cardiomyocytes and compared the gene expression profiles with those from primary adult murine cardiomyocytes and left ventricular myocardium.
Project description:To analyse the transcriptome landscape of differentiating cardiomyocytes, GFP labeled cardiac cells were purified by fluorescent activated cell sorting using the TinC*>GFP transgenic line, and expression profile analysed by deep sequencing.
Project description:A novel ppp1r13l sequence variation causes dilated cardiomyopathy and cardiac inflammation. In this experiment we knocked down IASPP (protein product of ppp1r13l) in cardiomyocytes and exposed them to lipopolysaccharide for time interval of 2 and 4 hours. Transcriptome was examined using rna-seq high-throughput sequencing.
