(A) Schematic diagram of GCKR variant association with glucokinase (GCK). GCKR functions as an inhibitor of GCK in the liver. The TT variant of GCKR-rs1260326 has a reduced ability to bind GCK and is less effective in suppressing GCK activities. (B) The time-course dynamics of GCK activity in HLOs carrying GCKRCC, GCKRCC>TT
(gene-edited), GCKRTT. Data are shown as means ± SD (error bars), n=4. (C) Measurement of GCK activity in GCKRCC, GCKRCC>TT, and GCKRTT-HLOs. Data are shown as mean ± SD (Error bars), n=4, in triplicate. Unpaired t-test; **p < 0.01, ***p < 0.001, ****p < 0.0001. (D) Representative images of de novo lipid accumulation in GCKRCC, GCKRCC>TT, and GCKRTT-HLOs. Images were stained with BODIPY for fat accumulation (Green) and Hoechst 33342 for the nucleus (Blue). Scale bars, low magnification: 300μm, high magnification: 50μm. (E) Quantification of de novo lipid accumulation in GCKRCC, GCKRCC>TT, and GCKRTT-HLOs. The intensity of lipid was normalized to nuclear signals (mean ± SD, n = 8 independent experiments). Unpaired t-test; ****p < 0.0001. (F) Mass-spec analysis of protein content-normalized levels of acetyl-CoA and palmitate in HLOs. Data are shown as mean ± SD (Error bars), n=3, Unpaired t-test; *p < 0.05. (G) Comparison of lipogenesis-associated gene expression in GCKRCC, GCKRCC>TT, and GCKRTT-HLOs. Data are shown as means ± SD. (error bars), n=4–8. Unpaired t-test; *p < 0.05, **p < 0.01, ***p < 0.001, ***p < 0.0001. (H) Imaging of de novo lipid accumulation in GCKRCC and GCKRTT-HLOs, treated with PFKFB3 inhibitor (PFK15), and GCK-GCKR disruptor (AMG3969). Images were stained with BODIPY for fat accumulation and Hoechst 33342 for the nucleus. Scale bars, low magnification: 100μm, high magnification: 50μm. (I) Quantification of de novo lipid accumulation in GCKRCC and GCKRTT HLOs treated with PFK15 or AMG3969. The intensity of lipid was normalized to nuclear signals (mean ± SD, n = 8 independent experiments). Unpaired t-test; *p < 0.05, ****p < 0.0001.