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报道了重金属离子Hg~(2+)对钙调神经磷酸酶(Calcineurin,CaN)活性的影响,得到以下结果:1.Hg~(2+)在有或无CaM存在时对纯化和部分纯化的CaN都有很强的激活作用,其激活程度大于已知的CaN最有效的激活剂Ni~(2+)2.Hg~(2+)的半激活浓度与Ca~(2+)在同一数量级,高浓度的Hg~(2+)则抑制CaN活性。3.Ca~(2+)的存在并不影响Hg~(2+)对CaN的进一步激活,同样Hg~(2+)的存在不影响Ca~(2+)的激活作用,提示二者的激活机制是不同的。4.CaM拮抗剂TFP对Hg~(2+)对CaN的激活仅表现微弱的抑制作用。5.在有或无CaM存在时,Hg~(2+)对CaN激活的最适pH为7.8。Hg~(2+)对CaN的活性影响为研究汞对神经系统的中毒作用又提供了新的线索。
The effect of heavy metal ion Hg 2+ on the activity of calcineurin (CaN) was reported. The following results were obtained: 1. The effect of Hg 2+ on the purification and partially purification of CaN has a strong activation, and its activation is greater than the known CaN most effective activator Ni ~ (2+) 2.Hg ~ (2+) half-activation concentration and Ca ~ (2+) in the same order of magnitude , While high concentrations of Hg 2+ inhibited CaN activity. The presence of Ca 2+ did not affect the further activation of CaN by Hg 2+. Similarly, the presence of Hg 2+ did not affect the activation of Ca 2+, Activation mechanism is different. CaM antagonist TFP showed weak inhibition on the activation of CaN by Hg 2+. 5. The optimum pH of Hg 2+ for CaN activation was 7.8 in the presence or absence of CaM. The effect of Hg 2+ on the activity of CaN provides new clues for studying the toxic effect of mercury on the nervous system.