Fig. 5: PUM1 regulates CRC growth by directly repressing p21.

a The mRNA levels of p21 in WT, Pum1^−/− and Pum2^−/− HCT116 cells (n = 3) as assayed by RT-qPCR. Actin was used as an internal control. Error bars represent SEM. b Western blot showing the p21 protein levels in WT, Pum1^−/− and Pum2^−/− HCT116 cells. Tubulin was used as a loading control. The bar graph shows the quantification of the western blot (n = 3). Error bars represent SD. c, d Enrichment of p21 mRNA by PUM1 RIP (c) or PUM2 RIP (d) in WT, Pum1^−/− or Pum2^−/− HCT116 cells (n = 3). Error bars represent SEM. e The p21 mRNA levels in WT, Pum1^−/− or Pum2^−/− HCT116 cells treated with actinomycin D (10 mg/ml) for the indicated period (n = 3). Error bars represent SEM. The bar graph shows the calculated p21 mRNA half-life (n = 3). Error bars represent SEM. f Schematic diagram of generating p21 PRE mutations in HCT116 cells. g DNA sequencing results of PRE in WT and p21 PRE^mut/mut cells. h Enrichment of p21 mRNA by PUM1 RIP in WT, Pum1^−/−, and p21 PRE^mut/mut HCT116 cells (n = 3). Error bars represent SEM. i The mRNA of p21 in WT, Pum1^−/− and p21 PRE^mut/mut HCT116 cells (n = 3). Actin mRNA was used as an internal control. Error bars represent SEM. j Western blot showing the p21 protein levels in WT, Pum1^−/− and p21 PRE^mut/mut HCT116 cells. GAPDH was used as a loading control. The bar graph shows the quantification of the western blot (n = 3). Error bars represent SD. k Images of colony formation assay in WT, Pum1^−/− and p21 PRE^mut/mut HCT116 cells. l Bar graph showing the colony numbers in each view in k (n = 3). Error bars represent SD. m Growth curve of WT, Pum1^−/−, and p21 PRE^mut/mut HCT116 cells (n = 3). Error bars represent SD. n Cell doubling time of WT, Pum1^−/−, and p21 PRE^mut/mut HCT116 cells (n = 3). Error bars represent SD. o Cell cycle analysis of WT, Pum1^−/−, and p21 PRE^mut/mut HCT116 cells (n = 3). Error bars represent SD. Source data are provided as a Source Data file.