Martins-Marques Tania, Anjo Sandra Isabel, Pereira Paulo, Manadas Bruno, Girão Henrique
From the ‡Institute of Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Azinhaga de Sta Comba, 3000-354 Coimbra, Portugal;
§CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; ¶Faculty of Sciences and Technology, University of Coimbra, 3030-790 Coimbra, Portugal;
Mol Cell Proteomics. 2015 Nov;14(11):3040-55. doi: 10.1074/mcp.M115.052894. Epub 2015 Aug 27.
The coordinated and synchronized cardiac muscle contraction relies on an efficient gap junction-mediated intercellular communication (GJIC) between cardiomyocytes, which involves the rapid anisotropic impulse propagation through connexin (Cx)-containing channels, namely of Cx43, the most abundant Cx in the heart. Expectedly, disturbing mechanisms that affect channel activity, localization and turnover of Cx43 have been implicated in several cardiomyopathies, such as myocardial ischemia. Besides gap junction-mediated intercellular communication, Cx43 has been associated with channel-independent functions, including modulation of cell adhesion, differentiation, proliferation and gene transcription. It has been suggested that the role played by Cx43 is dictated by the nature of the proteins that interact with Cx43. Therefore, the characterization of the Cx43-interacting network and its dynamics is vital to understand not only the molecular mechanisms underlying pathological malfunction of gap junction-mediated intercellular communication, but also to unveil novel and unanticipated biological functions of Cx43. In the present report, we applied a quantitative SWATH-MS approach to characterize the Cx43 interactome in rat hearts subjected to ischemia and ischemia-reperfusion. Our results demonstrate that, in the heart, Cx43 interacts with proteins related with various biological processes such as metabolism, signaling and trafficking. The interaction of Cx43 with proteins involved in gene transcription strengthens the emerging concept that Cx43 has a role in gene expression regulation. Importantly, our data shows that the interactome of Cx43 (Connexome) is differentially modulated in diseased hearts. Overall, the characterization of Cx43-interacting network may contribute to the establishment of new therapeutic targets to modulate cardiac function in physiological and pathological conditions. Data are available via ProteomeXchange with identifier PXD002331.
协调性和同步性的心肌收缩依赖于心肌细胞之间高效的缝隙连接介导的细胞间通讯（GJIC），这涉及通过含连接蛋白（Cx）的通道进行快速各向异性冲动传播，即通过心脏中最丰富的Cx43。不出所料，影响Cx43通道活性、定位和周转的干扰机制与几种心肌病有关，如心肌缺血。除了缝隙连接介导的细胞间通讯外，Cx43还与非通道依赖性功能有关，包括调节细胞粘附、分化、增殖和基因转录。有人提出，Cx43所起的作用取决于与Cx43相互作用的蛋白质的性质。因此，表征Cx43相互作用网络及其动态对于理解缝隙连接介导的细胞间通讯病理功能障碍的分子机制以及揭示Cx43新的和意想不到的生物学功能至关重要。在本报告中，我们应用定量SWATH-MS方法来表征大鼠心脏在缺血和缺血再灌注情况下的Cx43相互作用组。我们的结果表明，在心脏中，Cx43与参与各种生物学过程（如代谢、信号传导和运输）的蛋白质相互作用。Cx43与参与基因转录的蛋白质之间的相互作用强化了Cx43在基因表达调控中起作用这一新兴概念。重要的是，我们的数据表明，在患病心脏中，Cx43的相互作用组（连接体）受到不同的调节。总体而言，表征Cx43相互作用网络可能有助于建立新的治疗靶点，以在生理和病理条件下调节心脏功能。数据可通过ProteomeXchange获得，标识符为PXD002331。
