Oxidative stress-induced autonomous activation of the calcium/calmodulin-dependent kinase II involves disulfide formation in the regulatory domain.
Oxidative stress-induced autonomous activation of the calcium/calmodulin-dependent kinase II involves disulfide formation in the regulatory domain.
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DOI：
10.1016/j.jbc.2022.102579
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发表时间：
2022-11
影响因子：
4.8
通讯作者：
Levine, Rodney L.
中科院分区：
文献类型：
--
作者：
Rocco-Machado, Nathalia;Lai, Lo;Kim, Geumsoo;He, Yi;Luczak, Elizabeth D.;Anderson, Mark E.;Levine, Rodney L.
钙/钙调素依赖性蛋白激酶II δ（CaMK II δ）在心脏信号传导中具有关键作用。组成性和有害的CaMKII“自主”激活是由氧化应激诱导的，并且先前报道的机制涉及调节结构域中的甲硫氨酸残基的氧化。在这里，我们证明，共价氧化导致二硫键与Cys 273在调节域引起自主活动。用二酰胺或组胺氯胺（两种硫醇氧化剂）处理CaMKII诱导自主激活。当蛋白质与DTT或硫氧还蛋白孵育以还原二硫键时，自主性被逆转。激活的CaMKII的胰蛋白酶图谱显示在调节结构域中Cys 273和Cys 290之间形成二硫键。我们测定了这些Cys的表观PKa，发现Cys 273的PKa较低，而Cys 290的PKa升高。Cys 273的低pKa促进其硫醇在生理pH下氧化成次磺酸。反应性次磺酸然后攻击Cys 290的硫醇以形成二硫化物。先前报道的CaMKII突变体，其中甲硫氨酸残基281和282突变为缬氨酸（MMVV）保护小鼠和苍蝇免受氧化应激诱导的心脏代偿失调。我们最初的假设是MMVV突变体发生了构象变化，阻止了二硫键的形成和自主激活。然而，我们发现，硫醇氧化剂诱导自主性的MMVV突变体和突变体经历快速降解的细胞，潜在地防止积累的有害的自主形式。总之，我们的研究结果突出了CaMKII自主激活的其他机制细节。
Calcium/calmodulin-dependent protein kinase II δ (CaMKIIδ) has a pivotal role in cardiac signaling. Constitutive and deleterious CaMKII “autonomous” activation is induced by oxidative stress, and the previously reported mechanism involves oxidation of methionine residues in the regulatory domain. Here, we demonstrate that covalent oxidation leads to a disulfide bond with Cys273 in the regulatory domain causing autonomous activity. Autonomous activation was induced by treating CaMKII with diamide or histamine chloramine, two thiol-oxidizing agents. Autonomy was reversed when the protein was incubated with DTT or thioredoxin to reduce disulfide bonds. Tryptic mapping of the activated CaMKII revealed formation of a disulfide between Cys273 and Cys290 in the regulatory domain. We determined the apparent pKa of those Cys and found that Cys273 had a low pKa while that of Cys290 was elevated. The low pKa of Cys273 facilitates oxidation of its thiol to the sulfenic acid at physiological pH. The reactive sulfenic acid then attacks the thiol of Cys290 to form the disulfide. The previously reported CaMKII mutant in which methionine residues 281 and 282 were mutated to valine (MMVV) protects mice and flies from cardiac decompensation induced by oxidative stress. Our initial hypothesis was that the MMVV mutant underwent a conformational change that prevented disulfide formation and autonomous activation. However, we found that the thiol-oxidizing agents induced autonomy in the MMVV mutant and that the mutant undergoes rapid degradation by the cell, potentially preventing accumulation of the injurious autonomous form. Together, our results highlight additional mechanistic details of CaMKII autonomous activation.
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影响因子：
5
作者：
Luczak, Elizabeth D.;Anderson, Mark E.
通讯作者：
Anderson, Mark E.
影响因子：
5
作者：
Feng N;Anderson ME
通讯作者：
Anderson ME
影响因子：
64.5
作者：
Erickson, Jeffrey R.;Joiner, Mei-ling A.;Anderson, Mark E.
通讯作者：
Anderson, Mark E.
影响因子：
5
作者：
Chen, Wei-Jan;Chang, Shang-Hung;Yeh, Yung-Hsin
通讯作者：
Yeh, Yung-Hsin
影响因子：
15.9
作者：
Konstantinidis, Klitos;Bezzerides, Vassilios J.;Anderson, Mark E.
通讯作者：
Anderson, Mark E.