Serendipitous discovery of a novel protein signaling mechanism in heart failure.
Serendipitous discovery of a novel protein signaling mechanism in heart failure.
复制标题
心力衰竭中一种新的蛋白质信号传导机制的偶然发现。
DOI：
10.1016/j.bbrc.2012.03.124
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发表时间：
2012
影响因子：
3.1
通讯作者：
Walker,LoriA
中科院分区：
文献类型：
--
作者：
Vitello,AndreaM;Du,Yanmei;Buttrick,PeterM;Walker,LoriA
已知许多蛋白质信号传导机制参与心力衰竭的进展，但心力衰竭的机制仍知之甚少。因此，我们对这个问题采取了全面的方法，并使用抗体微阵列来识别在牛心力衰竭模型中功能障碍的右心室中差异表达的蛋白质，并使用来自牛和人类心力衰竭的心脏组织验证了结果。我们发现，蛋白质二硫键异构酶 3（PDIA3）是一种存在于内质网腔中的蛋白质，在左右心力衰竭的动物和人类模型中显着上调。此前尚未在心力衰竭模型中描述过该蛋白表达的改变。在我们最初的微阵列分析中，我们发现 CSK（c-Src 激酶）是衰竭牛心室中表达上调的蛋白质之一。为了进一步阐明 CSK 在心力衰竭中的作用，我们研究了其下游靶标 Src 的表达，发现心力衰竭的 Src 表达和磷酸化显着上调。然而，我们还注意到一种较小的免疫反应蛋白，仅在实验动物中发现。为了积极鉴定较小的 Src 反应蛋白，我们使用了二维凝胶电泳和质谱法。令人惊讶的是，我们将这种蛋白质鉴定为 PDIA3，一种不属于 Src 蛋白质家族的蛋白质。经过序列检查，我们发现 PDIA3 包含与 Src 具有很强同源性的短 C 端序列，并且正是针对该短序列生成了抗体。 PDIA3 参与 MHC I 类表达，并与风湿性心脏病中瓣膜功能障碍的进展以及肌浆网中的钙调节有关。该分子存在于内质网腔内，通过与钙联蛋白和钙网蛋白相互作用，参与蛋白质折叠过程中二硫键的形成。这种相互作用可能间接影响 SERCA（肌浆/内质网 Ca2+ 转运 ATP 酶）活性，并进一步导致钙失调，而钙失调是进行性心力衰竭的特征。需要进一步的研究来阐明 PDIA3 在心力衰竭进展中可能发挥的作用。
A number of protein signaling mechanisms are known to be involved in the progression of heart failure, yet the mechanism(s) by which the heart fails remains poorly understood. Therefore, we undertook a global approach to this question and used an antibody microarray to identify proteins differentially expressed in dysfunctional right ventricles in a bovine model of heart failure and the results were validated using cardiac tissue from both bovine and human heart failure. We found that protein disulfide isomerase 3, PDIA3, a protein that resides in the lumen of the endoplasmic reticulum, is significantly upregulated in both animal and human models of right and left heart failure. Altered expression of this protein has not previously been described in models of heart failure. In our initial microarray analysis, we found that CSK (c-Src kinase) was among the proteins upregulated in failing bovine ventricle. To further elucidate the role of CSK in heart failure, we studied the expression of its downstream target, Src, and found that Src expression and phosphorylation were markedly upregulated in failing ventricles. However, we also noted a smaller immunologically reactive protein that was only seen in experimental animals. In order to positively identify the smaller, Src-reactive protein, we used 2-dimensional gel electrophoresis and mass spectrophotometry. Surprisingly, we identified this protein as PDIA3, a protein that did not belong to the Src family of proteins. Upon sequence examination we found that PDIA3 contains a short C-terminal sequence with strong homology to Src and that it was this short sequence to which the antibody was generated. PDIA3 participates in MHC class I presentation and is implicated in the progression of valvular dysfunction in rheumatic heart disease, as well as calcium modulation in the sarcoplasmic reticulum. The molecule resides in the lumen of the endoplasmic reticulum and participates in disulfide bond formation during protein folding by interacting with calnexin and calreticulin. This interaction may indirectly effect SERCA (sarco/endoplasmic reticulum Ca2+-transport ATPase) activity and by extension contribute to the calcium dysregulation that characterizes progressive heart failure. Further studies are needed to elucidate the role that PDIA3 may play in the progression of heart failure.