L-Plastin S-glutathionylation promotes reduced binding to β-actin and affects neutrophil functions
L-Plastin S-glutathionylation promotes reduced binding to β-actin and affects neutrophil functions
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DOI：
10.1016/j.freeradbiomed.2015.04.008
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发表时间：
2015-09-01
影响因子：
7.4
通讯作者：
Dikshit, Madhu
中科院分区：
文献类型：
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作者：
Dubey, Megha;Singh, Abhishek K.;Dikshit, Madhu
细胞骨架蛋白的翻译后修饰（PTM）由于与几种病理条件相关的氧化应激通常会导致细胞功能的改变。本研究评价了一氧化氮（NO2-NO）诱导的人中性粒细胞氧化应激相关的细胞骨架蛋白S-谷胱甘肽化的作用。通过使用体外和遗传方法，我们表明，5-谷胱甘肽化的L-纤维蛋白酶（LPL）和β-肌动蛋白促进减少趋化性，极化，杀菌活性，和吞噬作用。我们鉴定了Cys-206、Cys-283和Cys-460为LPL的β-肌动蛋白结合结构域中的S-硫醇化残基，其中Cys-460具有最大得分。LPL Cys-460的定点突变进一步证实了LPL在氧化还原调节中的作用。S-硫醇化降低了LPL的结合以及捆绑活性。在来自糖尿病患者和PMN功能受损的db/db小鼠的中性粒细胞中检测到S-硫醇化LPL的存在。因此，增强的氮氧化应激可能导致LPL S-谷胱甘肽化，从而导致人类中性粒细胞的趋化性、极化和杀菌活性受损，为它们在糖尿病中的功能受损提供了机制基础。(C)2015 Elsevier Inc. All rights reserved.
Posttranslational modifications (PTMs) of cytoskeleton proteins due to oxidative stress associated with several pathological conditions often lead to alterations in cell function. The current study evaluates the effect of nitric oxide (DETA-NO)-incluced oxidative stress-related S-glutathionylation of cytoskeleton proteins in human PMNs. By using in vitro and genetic approaches, we showed that 5-glutathionylation of L-plastin (LPL) and beta-actin promotes reduced chemotaxis, polarization, bactericidal activity, and phagocytosis. We identified Cys-206, Cys-283, and Cys-460 as S-thiolated residues in the beta-actin-binding domain of LPL, where cys-460 had the maximum score. Site-directed mutagenesis of LPL Cys-460 further confirmed the role in the redox regulation of LPL. S-Thiolation diminished binding as well as the bundling activity of LPL The presence of S-thiolated LPL was detected in neutrophils from both diabetic patients and db/db mice with impaired PMN functions. Thus, enhanced nitroxidative stress may results in LPL S-glutathionylation leading to impaired chemotaxis, polarization, and bactericidal activity of human PMNs, providing a mechanistic basis for their impaired functions in diabetes mellitus. (C) 2015 Elsevier Inc. All rights reserved.