Fig. 4

Simulated and measured abundance profiles of species in our ERK-MAPK signaling model across human epidermis. Our model of the ERK-MAPK pathway is stimulated by: a normalized epidermal Ca²⁺ as derived by Mauro et al. [11]; and b plasma membrane CaM abundance as derived from our experimental data (Additional file 4: Figure S5i in CALM.png). At each spatial position, the model was run to steady-state with these inputs and c-g the simulated relative abundance of ERK-MAPK components is compared to our in situ experimental measurements. The y-axis in (a) has normalized units, and where experimental data is plotted (b-g), the y-axis represents the z-score of the immunofluorescence pixel intensities. The model input and output abundances were manually scaled to visually fit the experimental data by adjusting the baseline level and amplitude