S.3D Spatial Effect on Nuclear NF-kB OscillationFigure 4. The oscillation pattern is altered by the change in the nuclear transport. (A) There is a large change in the oscillation pattern by the change in the nuclear transport. Representative oscillations are shown in the right panels. (B) Oscillation frequency becomes larger as transport increases. (C) The amplitude of the first peak becomes larger at larger transport values. (D) The time to the first peak changed largely by the change in the transport. (E) tp and td also show large change by the change in the transport. These data are not available at smaller nuclear transport values. doi:10.1371/journal.pone.0046911.gThe change in the nuclear transport altered the oscillation pattern greatly, but differently from changes in the N/C ratio. The change in the number of NPCs can directly alter nuclear transport. In fact, it is reported that in tumor cell lines, Nup88, 1326631 a SR 3029 site component of NPC proteins, was strongly expressed, and its expression level correlated with malignancy [60,61]. These suggest the increased number of NPCs in cancer cells, and hence the increased nuclear transport. Together with these, our simulation results suggest altered oscillation patterns because of increased nuclear transport in cancer cells If we changed the spatial localization of IkBs transcription within a nucleus, there was no Triptorelin difference in the oscillation pattern from the control condition (Figure S3). If we changed the localization and the location of IKK activation, there was also no difference from the control conditions (Figure S4). These simulation results should be contrasted with those that have large effects on the oscillation pattern by changes in the N/C ratio, nuclear transport, location of IkBs synthesis, and the diffusion coefficient. If we look at the spatial distributions of nuclear NF-kB and cytoplasmic IKK in our simulation, they are virtually homogeneous (insets 15755315 in Figure S1A and S4B). These indicate thatNF-kB and IKK are well stirred, and this explains the unaltered oscillation pattern by changes in these spatial parameters. In the present report, we show an altered oscillation pattern of nuclear NF-kB due to changes in spatial parameters, the N/C ratio and nuclear transport that are strongly related to cancer cells. Therefore, it will be important to investigate these spatial parameters in normal and cancer cells.Materials and Methods Construction of Computational modelConstruction of both temporal and 3D models was performed using A-Cell software [66,67]. Models and all parameters used in the present study can be downloaded from http://www.ims.utokyo.ac.jp/mathcancer/A-Cell/index.html. Our temporal model is basically the same as Hoffmann’s model [23] which is shown in Figure 1A. The models for NF-kB activation comprise formation of IKK-IkB-NFkB complexes, degradation of IkBa, nuclear localization of freed NF-kB, NFkB transcription of IkBa mRNA, IkBs protein synthesis, and nuclear export of IkB-NF-kB complex (Figure S5).3D Spatial Effect on Nuclear NF-kB OscillationFigure 5. The oscillation pattern is affected by the change in the diffusion coefficient. (A) There are large changes in the oscillation pattern at low and high diffusion coefficients. At low diffusion coefficients, virtually no oscillation is seen. Right panels show representative oscillations. (B) At diffusion coefficients from 10212 to 10211 m2/s, the oscillation frequency stays unchanged. At higher diffusion coefficient, how.S.3D Spatial Effect on Nuclear NF-kB OscillationFigure 4. The oscillation pattern is altered by the change in the nuclear transport. (A) There is a large change in the oscillation pattern by the change in the nuclear transport. Representative oscillations are shown in the right panels. (B) Oscillation frequency becomes larger as transport increases. (C) The amplitude of the first peak becomes larger at larger transport values. (D) The time to the first peak changed largely by the change in the transport. (E) tp and td also show large change by the change in the transport. These data are not available at smaller nuclear transport values. doi:10.1371/journal.pone.0046911.gThe change in the nuclear transport altered the oscillation pattern greatly, but differently from changes in the N/C ratio. The change in the number of NPCs can directly alter nuclear transport. In fact, it is reported that in tumor cell lines, Nup88, 1326631 a component of NPC proteins, was strongly expressed, and its expression level correlated with malignancy [60,61]. These suggest the increased number of NPCs in cancer cells, and hence the increased nuclear transport. Together with these, our simulation results suggest altered oscillation patterns because of increased nuclear transport in cancer cells If we changed the spatial localization of IkBs transcription within a nucleus, there was no difference in the oscillation pattern from the control condition (Figure S3). If we changed the localization and the location of IKK activation, there was also no difference from the control conditions (Figure S4). These simulation results should be contrasted with those that have large effects on the oscillation pattern by changes in the N/C ratio, nuclear transport, location of IkBs synthesis, and the diffusion coefficient. If we look at the spatial distributions of nuclear NF-kB and cytoplasmic IKK in our simulation, they are virtually homogeneous (insets 15755315 in Figure S1A and S4B). These indicate thatNF-kB and IKK are well stirred, and this explains the unaltered oscillation pattern by changes in these spatial parameters. In the present report, we show an altered oscillation pattern of nuclear NF-kB due to changes in spatial parameters, the N/C ratio and nuclear transport that are strongly related to cancer cells. Therefore, it will be important to investigate these spatial parameters in normal and cancer cells.Materials and Methods Construction of Computational modelConstruction of both temporal and 3D models was performed using A-Cell software [66,67]. Models and all parameters used in the present study can be downloaded from http://www.ims.utokyo.ac.jp/mathcancer/A-Cell/index.html. Our temporal model is basically the same as Hoffmann’s model [23] which is shown in Figure 1A. The models for NF-kB activation comprise formation of IKK-IkB-NFkB complexes, degradation of IkBa, nuclear localization of freed NF-kB, NFkB transcription of IkBa mRNA, IkBs protein synthesis, and nuclear export of IkB-NF-kB complex (Figure S5).3D Spatial Effect on Nuclear NF-kB OscillationFigure 5. The oscillation pattern is affected by the change in the diffusion coefficient. (A) There are large changes in the oscillation pattern at low and high diffusion coefficients. At low diffusion coefficients, virtually no oscillation is seen. Right panels show representative oscillations. (B) At diffusion coefficients from 10212 to 10211 m2/s, the oscillation frequency stays unchanged. At higher diffusion coefficient, how.