Study of Z-disc protein interaction and signaling networks

最近发现的肌原纤维z盘的各种新成分为了解这种重要结构的分子结构和功能提供了有价值的见解。然而，可以合理地假设，z盘蛋白组的组成、蛋白-蛋白相互作用网络以及所涉及的动力学方面还远远没有被理解。除了鉴定新的Z-disc蛋白外，我们还着手准确表征肌原纤维蛋白质组和Z-disc相互作用组的动态变化，并研究与健康和疾病中Z-disc功能相关的不同细胞内信号通路。通过应用最新的定量（磷酸化）蛋白质组学方法，以高分辨率质谱（MS）为关键技术，我们将识别稳定和瞬时蛋白质-蛋白质相互作用，并监测蛋白质的可逆磷酸化事件和斑马鱼变形体中肌纤维蛋白质组的定量变化，其中给定Z-disc蛋白的表达下调。我们的研究结果将(1)补充z盘中单个蛋白质复合物（P1, P2， P5和P6）的结构分析和生化研究；(2)对调节Z-disc蛋白动态定位的信号通路的表征做出了重大贡献（P1）；(3)有助于更好地理解z盘在肌节稳定性和肌原纤维形成中的功能（P9）。

Recent discoveries of various new constituents of the myofibrillar Z-disc provided valuable insights into the molecular architecture and function of this vital structure. However, it is reasonable to assume that the composition of the Z-disc proteome, its protein-protein interaction network and the dynamic aspects involved are far from being comprehended. In addition to the identification of new Z-disc proteins, we thus set out to accurately characterize dynamic alterations in myofibrillar proteomes and the Z-disc interactome as well as to investigate distinct intracellular signalling pathways associated with Z-disc function in health and disease. Through application of latest quantitative (phospho)proteomic methodology with high-resolution mass spectrometry (MS) as key technology we will identify both stable and transient protein-protein interactions as well as monitor reversible phosphorylation events in proteins and quantitative changes in the myofibrillar proteome of zebrafish morphants, in which the expression of a given Z-disc protein is downregulated. Our results will (1) complement structural analyses and biochemical studies of individual protein complexes in the Z-disc (P1, P2, P5, and P6); (2) make a significant contribution to the characterization of signalling pathways regulating the dynamic localization of Z-disc proteins (P1); and (3) assist in a better understanding of Z-disc function in sarcomere stability and myofibrillogenesis (P9).