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+} signal, the penetrability of is found at an order of magnitude of }\mum, which is consistent with experimental observed calcium spike and wave. Our results suggest that the double messenger system may occur in the ER-PM junction to acquire great efficiency. The buffer effect of kinase is also discussed by calculating the average position of phosphorylations and free Ca^{2+ Ca^{2+} signal in intracellular space can be regulated through adjusting the initial speed of Ca^{2+ .