von Ossowski Lotta, Li Li-Li, Möykkynen Tommi, Coleman Sarah K, Courtney Michael J, Keinänen Kari
Department of Biosciences, Division of Biochemistry and Biotechnology, University of Helsinki, Helsinki, Finland.
Turku Centre for Biotechnology, Åbo Akademi University and University of Turku, Turku, Finland.
PLoS One. 2017 Feb 2;12(2):e0171489. doi: 10.1371/journal.pone.0171489. eCollection 2017.
Recent studies indicate that glutamatergic signaling involves, and is regulated by, thiol modifying and redox-active compounds. In this study, we examined the role of a reactive cysteine residue, Cys-893, in the cytosolic C-terminal tail of GluA1 AMPA receptor as a potential regulatory target. Elimination of the thiol function by substitution of serine for Cys-893 led to increased steady-state expression level and strongly reduced interaction with SAP97, a major cytosolic interaction partner of GluA1 C-terminus. Moreover, we found that of the three cysteine residues in GluA1 C-terminal tail, Cys-893 is the predominant target for S-nitrosylation induced by exogenous nitric oxide donors in cultured cells and lysates. Co-precipitation experiments provided evidence for native association of SAP97 with neuronal nitric oxide synthase (nNOS) and for the potential coupling of Ca2+-permeable GluA1 receptors with nNOS via SAP97. Our results show that Cys-893 can serve as a molecular target for regulatory thiol modifications of GluA1 receptors, including the effects of nitric oxide.
最近的研究表明，谷氨酸能信号传导涉及硫醇修饰和氧化还原活性化合物，并受其调节。在本研究中，我们检测了位于GluA1 AMPA受体胞质C末端的一个反应性半胱氨酸残基Cys-893作为潜在调节靶点的作用。用丝氨酸取代Cys-893消除硫醇功能，导致稳态表达水平升高，并显著降低与SAP97（GluA1 C末端主要的胞质相互作用伴侣）的相互作用。此外，我们发现，在GluA1 C末端的三个半胱氨酸残基中，Cys-893是培养细胞和裂解物中外源性一氧化氮供体诱导的S-亚硝基化的主要靶点。共沉淀实验为SAP97与神经元型一氧化氮合酶（nNOS）的天然结合以及Ca2+通透性GluA1受体通过SAP97与nNOS的潜在偶联提供了证据。我们的结果表明，Cys-893可作为GluA1受体调节性硫醇修饰的分子靶点，包括一氧化氮的作用。
