Figure 6(A) Luciferase-based quantification of MEF2 activity after Cand2 KD in NRCMs. Analysed by t-test, n=3 biological replicates. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (B) mRNA levels of MEF2-dependent genes Nr4a1 and Xirp2 in NRCMs with Cand2 KD for indicated groups. PE treatment for 24h (50uM). Analyzed by One-way ANOVA, n=6 biological replicates. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (C) mRNA levels of MEF2-dependent genes Nr4a1 and Xirp2 in NRCMs after Cand2 OE. Analyzed by t-test, n=7-8 biological replicates per conditions. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (D) RT-qPCR analysis of Xirp2 mRNA levels in LVs of WT and Cand2 KO mice after sham and TAC surgeries. Analyzed by One-way ANOVA, n=6-10 biological replicates per mice group. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (E) Grk5 protein and mRNA levels in NRCMs as well as MEF2-luciferase activity after 24h of Torin 1 treatment. Analyzed by t-test, n=4-6 biological replicates per conditions. Torin1 activity measured by protein levels of phosphorylated ribosomal S6 protein (S235/236rpS6). Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (F) Cand2 and Grk5 protein levels after TSC2 KD Analyzed by Western blot as well as MEF2-luciferase activity after TSC2 knockdown. Analyzed by t-test, n=5-6 biological replicates per conditions. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (G) Cand2 and Grk5 protein levels and Raptor transcript level in NRCMs after Raptor KD analyzed by Western blot. S235/236rpS6 - phosphorylated ribosomal S6 protein, downstream target of mTORC1. Analyzed by t-test, n=3 biological replicates Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (H) Quantifications of Cand2 and Grk5 protein levels level in NRCMs depleted of Raptor. Analyzed by t-test, n=3 biological replicates per conditions. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (I) Grk5, Nppa, and MEF2 targets Nr4a1 and Xirp2 mRNA levels in NRCMs after Raptor KD. Analyzed by t-test, n=3 biological replicates per conditions. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (J) Raptor and Grk5 protein levels after Raptor KD and adenoviral Grk5 overexpression. (K) Cell surface area measurement of NRCM for indicated groups. Analyzed by One-way ANOVA. n=3 independent experiments, n>150 cells. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001 (L) RT-qPCR analysis of MEF2 targets in NRCMs after Raptor KD and Grk5 overexpression. Analyzed by One-way ANOVA. n=6-8 biological replicates per conditions. Data information: Error bars indicate means ± SEM; * - P ≤ 0.05, ** - P ≤ 0.01, *** - P ≤ 0.001, **** - P ≤ 0.0001