Figure 2.

Expression of associated genes by RT-qPCR and western blotting after co-culture for 7 days. (A) HCN4, cTnT, Tbx3, Nkx2.5, Cx43 and Cx45 gene expression was examined using RT-qPCR. (B) HCN4, Cx43 and Cx45 protein expression examined using western blotting. (C) Quantitative assessment of HCN4, Cx43 and Cx45 protein levels by integrated optical density analyses. Similar results were obtained in three independent experiments. GAPDH was used as the protein control. *P<0.05 and **P<0.01 vs. GFP group. HCN4, hyperpolarization-activated cyclic nucleotide-gated cation channel 4; cTnT, cardiac troponin T; Tbx3, T-box 3; Nkx2.5, homeobox protein Nkx-2.5; Cx45, connexin 45; Cx43, connexin 43; GFP, green fluorescent protein; Tbx18, T-box 18; ISL-1, insulin gene enhancer binding protein 1; RT-qPCR, reverse transcription-quantitative polymerase chain reaction