Fig. 7: Constitutively active RBM24 phosphorylation induces cardiac abnormalities in mice with tamoxifen-inducible S181D RBM24.

a CRISPR/Cas9-mediated generation of Rbm24 S181D conditional KI mice at the ROSA26 locus in C57BL/6 mice. b Conditional Rbm24 S181D KI mice were injected with tamoxifen (TAM) or corn oil for 5 consecutive days, and RBM24 expression in hearts was analyzed by WB (n = 6). c Masson’s trichrome staining of heart sections from mice in (b). (n = 6), Scale bars, 1 mm. d Hearts weight/body weight (HW/BW) ratios of mice from (c) (n = 6). Two-tailed unpaired Student’s t-test. e Mice received TA-e2R-I or TA-e2R-S every 4 days for 30 days. Masson’s trichrome-stained heart sections (left) and fibrosis quantification (right) (n = 6). Scale bars, 50 μm. Two-tailed unpaired Student’s t-test. f Evans blue dye (EBD) uptake images (left) and damage area quantification (right) are shown 6 days after TA-e2R-I or TA-e2R-S injection (n = 6). Scale bars, 50 μm. Two-tailed unpaired Student’s t-test. g Troponin I (Tn-I) levels were measured in mice treated with TA-e2R-I or TA-e2R-S for 6 days (n = 6). Two-tailed unpaired Student’s t-test. h H9C2 cells were treated with different concentrations of Tat-e2R-I or scrambled e2R-S, and analyzed by WB (n = 3). i Mice were injected with TA-e2R-I or TA-e2R-S. After 6 h, heart tissue samples were analyzed by WB (n = 3). j Mice underwent social isolation for 5, 10, 20, and 30 days. Serum samples were collected and analyzed by WB. Congo red staining was used as a loading control (n = 5). k Serum samples were collected pre- or post-10h SI, enriched for phosphorylated proteins via IMAC (immobilized metal affinity chromatography), followed by WB analysis. Quantification of phosphorylation levels in serum was shown on the right (n = 10). Two-tailed unpaired Student’s t-test. l The analysis of receiver operating characteristic (ROC) curves demonstrated a significant association between phosphorylated RBM24 (p-RBM24) and psychological stress (area under curve, AUC = 0.94, p < 0.001). The AUC value, P value were determined by ROC curve analysis. m Schematic illustration of the study’s findings. Data were shown as mean ± SD (d–f, g, k) from six to ten independent experiments.