A549 in-silico 1.0: A first computational model to simulate cell cycle dependent ion current modulation in the human lung adenocarcinoma

Figures

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  Fig 1. Reported ion channels in the A549 cell line. For detailed review see S1 Text.

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  Fig 2. A549 whole-cell ion current model. The model illustrates the different ion channel types, macroscopic currents and kinetic schemes of the used hidden Markov models (HMM). Potassium channels, including Kv1.3, Kv3.1, Kv3.4, Kv7.1, TASK-1, KCA1.1 and KCa3.1 are represented in blue, green denotes the included calcium channels CRACM1, TRPV3 and TRPC6 and red represents the considered chloride channel CLC-2. See also S1 Fig. Created with BioRender.com.

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  Fig 3. Measured and simulated whole-cell current response. Averaged whole-cell current curves measured at voltage-steps from -40 mV to +40 mV for (A) cells with negative resting membrane potential, G0 phase (n = 11) and (B) positive resting membrane potential, G1 phase (n = 5). (C) Averaged current-voltage curve of cells in G0 phase (mean ± SD): -40 mV: -0.1114 ± 0.0850 nA, -30 mV: -0.0849 ± 0.0671 nA, -20 mV: -0.0514 ± 0.0454 nA, -10 mV: -0.0059 ± 0.0292 nA, 0 mV: 0.0464 ± 0.0113 nA, +10 mV: 0.1137 ± 0.0286 nA, +20 mV: 0.1903 ± 0.0560 nA, +30 mV: 0.2770 ± 0.0920 nA, +40 mV: 0.3644 ± 0.1327 nA. (D) Averaged current-voltage curve of cells in G1 phase: -40 mV: -0.1140 ± 0.1721 nA, -30 mV: -0.0900 ± 0.1310 nA, -20 mV: -0.0649 ± 0.0960 nA, -10 mV: -0.0364 ± 0.0467 nA, 0 mV: -0.0065 ± 0.0088 nA, +10 mV: 0.0294 ± 0.0516 nA, +20 mV: 0.0744 ± 0.1150 nA, +30 mV: 0.1233 ± 0.1968 nA, +40 mV: 0.1685 ± 0.2794 nA. Comparison of simulated whole-cell current kinetics (blue lines) and experimental data (black lines) for the applied voltage-step protocol, and the corresponding current-voltage curves for cells in the G0 phase (E, G) and for cells in the G1 phase (F, H). RMSE values for simulation of…

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  Fig 4. Resting potential, ramp potential and reversal potential in G0 and G1 cell cycle phase. Resting membrane potentials measured in current-clamp mode, reversal potentials from voltage-ramp measurements and derived reversal potentials from current-voltage curves in negative (G0 phase) and highly depolarized (G1 phase) A549 cells. Black lines in the boxplot indicate the median, white lines the mean value. Whiskers denote 10% and 90% percentiles. Single scores outside the 10% and 90% percentile are depicted as black circles. P-values demonstrate statistical significance between cells in G0 and G1 phase. Detailed measurement results are provided in S2 Table. Created with BioRender.com.

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  Fig 5. Model verification by experimental and synthetic data. Voltage-ramp currents measured at -100 mV to -40 mV (black lines) for (A) cells in G0 (n = 9) and (B) G1 (n = 4) phase, and corresponding model simulations (blue lines, RMSEG0 = 0.0314 and RMSEG1 = 0.0211). (C, D) Comparison of the whole-cell current of simulated sample cells (blue lines, n = 100) with averaged whole-cell current curves from activation protocols (black line, mean ± SD) in G0 and G1 phase.

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  Fig 6. Schematic illustration of the simulated ion channel activity during the A549 cell cycle. G0/G1 transition: modulation of ion channel activity predicted by the model approach. G1/S and S/G2 transition: simulation of ion channel activation and inactivation, responsible for A549 cell cycle progression. Calculated membrane potentials for G0, G1, S and G2 phase are illustrated by yellow dots: Vm_G0 = -10.4 mV, Vm_G1 = -1.33 mV, Vm_S = -13.3 mV, Vm_G2/M = -5.49 mV. The symbols + and - indicate activation and inactivation of ion channels.

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  Fig 7. Schematic illustration of model simulations of ion channel activation and inactivation during cell cycle progression. (A) Simulation of TASK-1 channel blockage in G1 phase. (B) Simulation of Kv1.3 channel blockage in a) G1 phase and b) during transition from G1 to S phase. (C) Simulation of Kv7.1 channel blockage starting at G1 phase. (D) Simulation of KCa3.1 channel blockage during G1-S transition. (E) Simulation of TRPC6 channel blockage in a) G0 phase and b) during transition from S to G2/M phase. The symbol + means activation, - means inactivation of ion channels.