Understanding the mechanisms of cross-talk between posttranslational modifications during growth factor signalling

细胞行为由一个复杂的细胞信号事件系统控制，其中包括改变蛋白质功能、活性或稳定性的翻译后修饰(PTM)。众所周知，两个这样的PTM之间的相互作用，即磷酸化和泛素化，在决定特定细胞结果方面发挥着重要作用，但关于这些修饰在某些细胞条件下的相互作用仍有许多需要了解。蛋白质组学技术的进步使全球范围内对磷酸化和泛素化事件的大规模分析成为可能。结合细胞培养中氨基酸稳定同位素标记(SILAC)等定量技术，可以研究特定细胞条件下大量修饰多肽丰度的变化。对于磷酸化和泛素化的多肽，可以使用同时浓缩策略来识别多肽的共同修饰，从而理解这两种修饰是如何交叉调节的。生长因子调控的信号通路依赖于翻译后修饰来控制生物反应的持续时间。成纤维细胞生长因子信号通路是调控细胞增殖、分化和存活等多种细胞过程的信号通路之一。已知泛素化事件在反馈环路中起作用，以衰减信号，尽管这些事件尚未在全球范围内进行研究。这个项目的目的是研究磷酸化和泛素化之间的串扰对成纤维细胞生长因子的反应，并了解这些修饰如何动态地共同作用，以微调相关的生物反应。

Cell behaviour is controlled by a complex system of cell signalling events that include post-translational modifications (PTMs) that alter the functionality, activity or stability of a protein. Cross talk between two such PTMs, phosphorylation and ubiquitination, is known to play an important role in determining specific cellular outcomes, however there is still much to learn about the interplay of these modification under certain cellular conditions. Advances in proteomics techniques have enabled large scale analysis of both phosphorylation and ubiquitination events on a global scale. Combined with quantitative techniques such as stable isotope labelling with amino acids in cell culture (SILAC), changes in the abundance of large numbers of modified peptides under specific cellular conditions can be investigated. Co-modification of peptides can be identified using concurrent enrichment strategies for both phosphorylated and ubiquitinated peptides, leading to an understanding of how these two modifications are cross-regulated. Growth factor regulated signalling pathways are reliant on post-translational modifications to control the duration of a biological response. The fibroblast growth factor (FGF) signalling pathway is one such pathway that mediates many cellular processes such as cell proliferation, differentiation and survival. Ubiquitination events are known to act in feedback loops to attenuate the signal, although these events have not been studied in a global context. The aim of this project is to study the cross talk between phosphorylation and ubiquitination in response to FGF and gain an understanding of how these modifications dynamically act together to finely tune the associated biological responses.