Proteomic and bioinformatic analysis of differentially expressed proteins in denervated skeletal muscle
Proteomic and bioinformatic analysis of differentially expressed proteins in denervated skeletal muscle
复制标题
去神经骨骼肌差异表达蛋白的蛋白质组学和生物信息学分析
DOI：
10.3892/ijmm.2014.1737
复制
发表时间：
2014-06-01
影响因子：
5.4
通讯作者：
Gu, Xiaosong
中科院分区：
文献类型：
--
作者：
Sun, Hualin;Qiu, Jiaying;Gu, Xiaosong
这项研究的目的是提高我们对失神经诱导的骨骼肌萎缩的认识和目前的治疗方法。用等压相对和绝对定量标记(ITRAQ)结合二维液相色谱-串联质谱仪(2DLC-MS/MS)鉴定坐骨神经切断后1周和4周大鼠胫骨前肌(TA)中差异表达的蛋白质。共有110个蛋白质进行了差异表达，并利用基因本体论(GO)和京都基因和基因组百科全书(KEGG)数据库中的术语进行了进一步分类，以揭示它们的分子功能。在参与糖酵解、Krebs循环和氧化磷酸化的差异表达代谢酶中，α-烯醇化酶和β-烯醇化酶的表达分别增加和降低，Western印迹分析和免疫组织化学进一步证实了这一点。这些发现表明，在失神经诱导的肌肉萎缩期间，烯醇酶同工酶的开关与肌肉成熟时的相反。值得注意的是，使用STRING数据库的蛋白质-蛋白质相互作用分析表明，在失神经诱导的骨骼肌萎缩过程中，肿瘤坏死因子受体：相关因子-6(TRAF6)、肌肉环指蛋白1(MuRF1)和肌肉萎缩F-box(MAFBx)的蛋白表达也上调，这一点经Western印迹分析证实。L6肌管的TRAF6基因敲除实验表明，TRAF6的表达减少可减轻糖皮质激素诱导的肌管萎缩。因此，我们推测TRAF6的上调可能至少部分通过调节MAFBx和MuRF1蛋白的表达而参与失神经诱导的肌肉萎缩的发生发展。本研究的数据为调控失神经诱导的肌肉萎缩的分子机制提供了有价值的见解。
The aim of this study was to improve our understanding and the current treatment of denervation-induced skeletal muscle atrophy. We used isobaric tags for relative and absolute quantification (iTRAQ) coupled with two-dimensional liquid chromatography-tandem mass spectrometry (2DLC-MS/MS) to identify the differentially expressed proteins in the tibialis anterior (TA) muscle of rats at 1 and 4 weeks following sciatic nerve transection. A total of 110 proteins was differentially expressed and was further classified using terms from the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases to unravel their molecular functions. Among the differentially expressed metabolic enzymes involved in glycolysis, Krebs cycle and oxidative phosphorylation, alpha- and beta-enolase displayed an increased and decreased expression, respectively, which was further validated by western blot analysis and immunohistochemistry. These findings suggest that the enolase isozymic switch during denervation-induced muscle atrophy is the reverse of that occurring during muscle maturation. Notably, protein-protein interaction analysis using the STRING database indicated that the protein expression of tumor necrosis factor receptor:associated factor-6 (TRAF6), muscle ring-finger protein 1 (MuRF1) and muscle atrophy F-box (MAFBx) was also upregulated during denervation-induced skeletal muscle atrophy, which was confirmed by western blot analysis. TRAF6 knockdown experiments in L6 myotubes suggested that the decreased expression of TRAF6 attenuated glucocorticoid-induced myotube atrophy. Therefore, we hypothesized that the upregulation of TRAF6 may be involved in the development of denervation-induced muscle atrophy, at least in part, by regulating the expression of MAFBx and MuRF1 proteins. The data from the present study provide valuable insight into the molecular mechanisms regulating denervation-induced muscle atrophy.