Nitric oxide regulation of MMP-9 activation and its relationship to modifications of the cysteine switch
Nitric oxide regulation of MMP-9 activation and its relationship to modifications of the cysteine switch
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DOI：
10.1021/bi702496v
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发表时间：
2008-05-27
期刊：
影响因子：
2.9
通讯作者：
van der Vliet, Albert
中科院分区：
文献类型：
--
作者：
McCarthy, Sean M.;Bove, Peter F.;van der Vliet, Albert
基质金属蛋白酶（MMP）是参与细胞外基质组分降解的含Zn内肽酶，并且通常以潜伏（pro-MMP）形式分泌，并通过保守半胱氨酸开关的蛋白水解或氧化破坏而活化。最近的一些研究表明，一氧化氮（NO）可以促进MMPs的激活，但所涉及的机制尚不完全清楚。我们研究了NO调节MMP-9激活的能力，使用各种NO供体化合物，并使用代表MMP-9半胱氨酸开关结构域的合成肽（PRCGVPDLGR）表征半胱氨酸开关的修饰。在所用的NO供体中，发现仅S-亚硝基半胱氨酸（SNOC）能够适度激活proMMP-9，但S-亚硝基谷胱甘肽（GSNO）或NONOates、DEA-NO、SPER-NO或NONO-NO无效。事实上，发现高浓度的β-NO抑制MMP-9活性，推测是通过与活性位点Zn 2+的直接相互作用。分析含Cys肽PRCGVPDLGR内的化学修饰。揭示了通过SNOC和GSNO的快速和瞬时S-亚硝基化，以及作为主要终产物的混合二硫化物和二聚肽的形成。类似地，NONOates诱导瞬时S-亚硝基化和主要的肽二聚化。肽Cys与合成的Zn 2+复合物的配位，以更接近地模拟proMMP-9中的活性位点的结构，减少肽亚硝基化和NONOates的氧化，但增强SNOC和GSNO的肽亚硝基化。总的来说，我们的研究结果表明，NO是不能直接激活MMP-9和S-亚硝基化的MMP-9前肽NO供体是无关的，他们的能力，调节MMP-9的活性。
Matrix metalloproteases (MMPs) are Zn-containing endopeptidases involved in the degradation of extracellular matrix components and are typically secreted in a latent (pro-MMP) form and activated either by proteolytic or oxidative disruption of a conserved cysteine switch. Several recent studies have suggested that nitric oxide (NO) can contribute to the activation of MMPs, but the mechanisms involved are incompletely understood. We investigated the ability of NO to regulate the activation of (pro)MMP-9 using a variety of NO-donor compounds and characterized modifications of the cysteine switch using a synthetic peptide (PRCGVPDLGR) representing the cysteine switch domain of MMP-9. Among the NO-donors used, only S-nitrosocysteine (SNOC) was found to be capable of modest activation of proMMP-9, but S-nitrosoglutathione (GSNO) or the NONOates, DEA-NO, SPER-NO, or DETA-NO, were ineffective. In fact, high concentrations of DETA-NO were found to inhibit MMP-9 activity, presumably by direct interaction with the active-site Zn2+. Analysis of chemical modifications within the Cys-containing peptide, PRCGVPDLGR,. revealed rapid and transient S-nitrosylation by SNOC and GSNO, and formation of mixed disulfides and dimerized peptide as major final products. Similarly, NONOates induced transient S-nitrosylation and primarily peptide dimerization. Coordination of the peptide Cys with a synthetic Zn2+ complex, to more closely mimic the structure of the active site in proMMP-9, reduced peptide nitrosylation and oxidation by NONOates, but enhanced peptide nitrosylation by SNOC and GSNO. Collectively, our results demonstrate that NO is incapable of directly activating proMMP-9 and that S-nitrosylation of MMP-9 propeptide by NO-donors is unrelated to their ability to regulate MMP-9 activity.