Klee C B, Crouch T H, Krinks M H
Proc Natl Acad Sci U S A. 1979 Dec;76(12):6270-3. doi: 10.1073/pnas.76.12.6270.
The inhibitory protein that binds calmodulin and thus prevents activation of several Ca2+-dependent enzymes by calmodulin is shown to also bind four Ca2+ per mol of protein with high affinity (Kd less than or equal to 10(-6) M). On the basis of its Ca2+- binding properties and its localization to nervous tissue, the inhibitory protein is now called "calcineurin." Calcineurin is composed of two subunits: calcineurin A (61,000 Mr) which interacts with calmodulin in a Ca2+-dependent fashion, and calcineurin B (15,000 Mr) which binds Ca2+. The interaction of calcineurin A with calcineurin B is independent of Ca2+ or Mg2+. The dual interaction of calcineurin A with two different Ca2+-binding components and the high affinity of calcineurin for Ca2+ suggest a possible role for calcineurin in the regulation of free Ca2+ concentrations in the nervous system. Calcineurin may thereby modulate the release and action of neurotransmitters.
已证明，这种与钙调蛋白结合从而阻止钙调蛋白激活多种钙依赖性酶的抑制蛋白，每摩尔蛋白还能以高亲和力（解离常数Kd≤10⁻⁶ M）结合4个钙离子。基于其钙离子结合特性及其在神经组织中的定位，这种抑制蛋白现在被称为“钙调神经磷酸酶”。钙调神经磷酸酶由两个亚基组成：钙调神经磷酸酶A（分子量61,000），它以钙依赖性方式与钙调蛋白相互作用；以及钙调神经磷酸酶B（分子量15,000），它结合钙离子。钙调神经磷酸酶A与钙调神经磷酸酶B的相互作用不依赖于钙离子或镁离子。钙调神经磷酸酶A与两种不同钙离子结合成分的双重相互作用以及钙调神经磷酸酶对钙离子的高亲和力，表明钙调神经磷酸酶在调节神经系统中游离钙离子浓度方面可能发挥作用。钙调神经磷酸酶可能由此调节神经递质的释放和作用。
