Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, Paris, France.
Antioxid Redox Signal. 2012 Mar 15;16(6):567-86. doi: 10.1089/ars.2011.4255. Epub 2011 Dec 20.
In photosynthetic organisms, besides the well-established disulfide/dithiol exchange reactions specifically controlled by thioredoxins (TRXs), protein S-glutathionylation is emerging as an alternative redox modification occurring under stress conditions. This modification, consisting of the formation of a mixed disulfide between glutathione and a protein cysteine residue, can not only protect specific cysteines from irreversible oxidation but also modulate protein activities and appears to be specifically controlled by small disulfide oxidoreductases of the TRX superfamily named glutaredoxins (GRXs).
In recent times, several studies allowed significant progress in this area, mostly due to the identification of several plant proteins undergoing S-glutathionylation and to the characterization of the molecular mechanisms and the proteins involved in the control of this modification.
This article provides a global overview of protein glutathionylation in photosynthetic organisms with particular emphasis on the mechanisms of protein glutathionylation and deglutathionylation and a focus on the role of GRXs. Then, we describe the methods employed for identification of glutathionylated proteins in photosynthetic organisms and review the targets and the possible physiological functions of protein glutathionylation.
In order to establish the importance of protein S-glutathionylation in photosynthetic organisms, future studies should be aimed at delineating more accurately the molecular mechanisms of glutathionylation and deglutathionylation reactions, at identifying proteins undergoing S-glutathionylation in vivo under diverse conditions, and at investigating the importance of redoxins, GRX, and TRX, in the control of this redox modification in vivo.
在光合作用生物中，除了由硫氧还蛋白（TRX）专门控制的众所周知的二硫键/巯基交换反应外，蛋白质 S-谷胱甘肽化作为一种替代的氧化还原修饰，在应激条件下出现。这种修饰由谷胱甘肽和蛋白质半胱氨酸残基之间形成的混合二硫键组成，不仅可以保护特定的半胱氨酸免受不可逆氧化，还可以调节蛋白质活性，并且似乎由 TRX 超家族的小二硫键氧化还原酶命名为谷胱甘肽还原酶（GRX）专门控制。
最近，由于鉴定了几种发生 S-谷胱甘肽化的植物蛋白，以及对控制这种修饰的分子机制和涉及的蛋白质进行了表征，该领域取得了重大进展。
本文对光合作用生物中的蛋白质谷胱甘肽化进行了全面概述，特别强调了蛋白质谷胱甘肽化和去谷胱甘肽化的机制，并重点介绍了 GRX 的作用。然后，我们描述了在光合作用生物中鉴定谷胱甘肽化蛋白所采用的方法，并回顾了谷胱甘肽化蛋白的靶标和可能的生理功能。
为了确定蛋白质 S-谷胱甘肽化在光合作用生物中的重要性，未来的研究应旨在更准确地描绘谷胱甘肽化和去谷胱甘肽化反应的分子机制，在不同条件下体内鉴定发生 S-谷胱甘肽化的蛋白质，并研究氧化还原酶、GRX 和 TRX 在体内控制这种氧化还原修饰的重要性。
