Carbon Nanoparticles Enhance Potassium Uptake via Upregulating Potassium Channel Expression and Imitating Biological Ion Channels in BY-2 Cells

Abstract Background: Carbon nanoparticles (CNPs) have been reported to boost plant growth, while CNPs enhancing potassium uptake for plant growth have not been reported so far.Results: In this study, the function of CNPs promoting potassium uptake in BY-2 cells was established and the potassium accumulation in cells has a significant correlation relationship with BY-2 cell fresh biomass. The K + accumulation in cells increased with the increasing concentration of CNPs. The K + influx reached high level after treatment with CNPs and exhibited significantly higher than the control group and the negative group treated with K + channels blocker, tetraethylammonium chloride (TEA + ). The K + accumulation was not reduced in the presence of CNPs inhibitors. In presence of the potassium channel blocker TEA + and the CNPs inhibitors, NKT1 expression was downregulated. The CNPs were found to preferentially transport K + than other cations determined by rectification of ion current assay (RIC) in a conical nanocapillary.Conclusions: These results indicated that CNPs upregulated potassium gene expression to enhance K + accumulation in BY-2 cells. Moreover, it was speculated that the CNPs simulated protein ion channels via bulk of carboxyl for K + permeating. These findings will provide support for improving plant growth by carbon nanoparticles.