Fig. 1: The influence of copper on cell cycle G2/M progression.

a Flow cytometric analysis of the impact of copper on cell cycle progression in CTR1 knocked-down HepG2 cells. After synchronization to the S phase by 2.5 mM TdR, cells were released and cultured for 12 h. The percentages of different cell cycle stages are quantified on the right. The same treatment condition was used hereafter, if not specifically noted. b The schematic representation of FUCCI reporter system. Magenta: G1 phase; bright green: G2/M phase. c FUCCI reporter assay assessing the cell cycle progression of CTR1 knocked-down HepG2 cells. Scale bars are 50 μm. d, e Examination of the effect of copper-binding deficiencies of CTR1 on cell cycle progression using flow cytometry and FUCCI assay. Scale bars are 50 μm. f, g Flow cytometry (f) and FUCCI reporter assay (g) analyzing copper’s impact on cell cycle progression of HepG2 cells under different treatments. The cells were synchronized to the S phase using TdR and cultured in metal-deprived medium without or with copper (-Metal or Cu, respectively), or cultured in regular medium containing 20 μM TEPA or 50 μM TTM for 12 h. Scale bars represent 50 μm. In (a, d, f), data are representative of three biologically independent experiments. Source data are provided as a Source Data file.