Dynamic simulation of the effect of calcium-release activated calcium channel on cytoplasmic Ca2+ oscillation.
A mathematical model is proposed to illustrate the activation of STIM1 (stromal interaction molecule 1) protein, the assembly and activation of calcium-release activated calcium (CRAC) channels in T cells. In combination with De Young-Keizer-Li-Rinzel model, we successfully reproduce a sustained Ca(2+) oscillation in cytoplasm. Our results reveal that Ca(2+) oscillation dynamics in cytoplasm can be significantly affected by the way how the Orai1 CRAC channel are assembled and activated. A low sustained Ca(2+) influx is observed through the CRAC channels across the plasma membrane. In particular, our model shows that a tetrameric channel complex can effectively regulate the total quantity of the channels and the ratio of the active channels to the total channels, and a period of Ca(2+) oscillation about 29 s is in agreement with published experimental data. The bifurcation analyses illustrate the different dynamic properties between our mixed Ca(2+) feedback model and the single positive or negative feedback models.
Chen
Xiao-fang
XF
Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
Li
Cong-xin
CX
Wang
Peng-ye
PY
Li
Ming
M
Wang
Wei-chi
WC
D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism*; D003198:Computer Simulation; D003593:Cytoplasm / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D011485:Protein Binding
D015220:Calcium Channels; D009363:Neoplasm Proteins; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium