The electromagnetic field (EMF) is newly considered as an exogenous environmental stimulus that is closely related to ion transportation on the cellular membrane, maintaining the internal ionic homeostasis. Cation transports of Ca2+ and other metal ions, Cd2+, Zn2+, and Mn2+were studied in terms of the external Ca2+ stress, [Ca2+]ext, and exposure to the physical EMF. A specific yeast strain K667 was used for controlling CAX5 (cation/H+ exchanger) expression. Culture samples were exposed to 60 Hz, 0.1 mT sinusoidal or square magnetics waves, and intracellular cations of each sample were measured and analyzed. AtCAX5 transformant yeast grew normally under the metallic stress. However, the growth of the control group was significantly inhibited under the same cation concentration; 60 Hz and 0.1 mT magnetic field enhanced intracellular cation concentrations significantly as exposure time increased both in the AtCAX5 transformed yeast and in the control group. However, the AtCAX5-transformed yeast showed higher concentration of the intracellular cations than the control group under the same exposure EMF. AtCAX5-transformed yeasts displayed an increment in [Ca2+]int, [K+]int, [Na+]int, and [Zn2+]int concentration under the presence of both sinusoidal and square-waved EMF stresses compared to the control group, which shows that AtCAX5 expressed in the vacuole play an important role in maintaining the homeostasis of intracellular cations. These findings could be utilized in the cultivation of the crops which were resistant to excessive exogenous ions or in the production of biomass containing a large proportion of ions for nutritional food or in the bioremediation process in metal-polluted environments.

中文翻译：

---

电磁场环境对 AtCAX5 转化酵母阳离子转运的影响

电磁场 (EMF) 被新认为是一种外源性环境刺激，与细胞膜上的离子运输密切相关，维持内部离子稳态。Ca2+ 和其他金属离子、Cd2+、Zn2+ 和 Mn2+ 的阳离子传输根据外部 Ca2+ 应力、[Ca2+]ext 和暴露于物理 EMF 进行了研究。特定酵母菌株 K667 用于控制 CAX5（阳离子/H+ 交换剂）表达。培养样品暴露于 60 Hz、0.1 mT 正弦或方磁波，并测量和分析每个样品的细胞内阳离子。AtCAX5 转化酵母在金属胁迫下正常生长。但在相同阳离子浓度下，对照组的生长明显受到抑制；60 赫兹和 0。随着 AtCAX5 转化酵母和对照组中暴露时间的增加，1 mT 磁场显着增强了细胞内阳离子浓度。然而，在相同的 EMF 暴露下，AtCAX5 转化的酵母显示出比对照组更高的细胞内阳离子浓度。与对照组相比，在存在正弦波和方波 EMF 应力的情况下，AtCAX5 转化的酵母显示出 [Ca2+]int、[K+]int、[Na+]int 和 [Zn2+]int 浓度的增加，这表明在液泡中表达的 AtCAX5 在维持细胞内阳离子的稳态中起重要作用。