Fig. 6: Foxk1 and Foxk2 induce cardiomyocyte proliferation by binding to the promoter regions of Ccnb1 and Cdk1, respectively.

A, B GO analysis of direct target genes from CUT&Tag-seq of Foxk1- or Foxk2-overexpressing cardiomyocytes. C Sankey diagram showing the direct target genes of FOXK1 from an overlay of CUT&Tag and RNA-seq profiles. D FOXK1, and FOXK2 CUT&Tag signals (normalized reads) in the Ccnb1 and Cdk1 locus, respectively. Filled boxes indicate peaks. E, F ChIP-PCR demonstrating the binding of FOXK1 to the Ccnb1 promoter region (E) and FOXK2 to the Cdk1 promoter region (F) (n = 3 per group). G, H qRT-PCR analysis showing the expression levels of Ccnb1 and Cdk1 in cardiomyocytes following overexpression of Foxk1 or Foxk2 (n = 4 per group). I, J Ccnb1, and Cdk1 transcript levels after knockdown of Foxk1 or Foxk2 in cardiomyocytes (n = 3 per group). K, L Western blot analysis of CCNB1 and CDK1 in cardiomyocytes following overexpression (K) and knockdown (L) of Foxk1 or Foxk2 (n = 3 per group). M, N Flow cytometry analysis of cell cycle distribution in Foxk1- and Foxk2-overexpressing cardiomyocytes (n = 4 per group). O, P Representative images and quantitative analysis of co-immunostaining of α-actinin (red) and pH3 (green, indicated by yellow arrows) in cardiomyocytes overexpressing Foxk1 with Ccnb1 knockdown (O), and in cardiomyocytes overexpressing Foxk2 with Cdk1 knockdown (P) (n = 3 per group). Data are presented as mean ± SEM. p values were determined by a two-sided Hypergeometric test (A, B), two-tailed unpaired t-test (E–J), two-way ANOVA with Bonferroni multiple comparisons test (N) and one-way ANOVA with Bonferroni multiple comparisons test (O, P). Source data are provided as a Source Data file.