Before revision:  To keep the locality of Ca^{2+} signal, the penetrability of is found at an order of magnitude of }\mum Ca^{2+} signal in intracellular space can be regulated through adjusting the initial speed of Ca^{2+ .
After revision:  To keep the locality of Ca^{2+} which is read out by phosphorylation is studied in two scenarios with simulation and mean field ansatz. The coverage of distribution of Ca^{2+ is found at an order of magnitude of }\mum Ca^{2+} signal in intracellular space can be regulated through adjusting the initial speed of Ca^{2+ .