Protein kinase D-mediated balance between lipid homeostasis and secretory activity in mammalian cells - A systemic appoach

蛋白激酶 D 介导的哺乳动物细胞脂质稳态和分泌活性之间的平衡 - 系统方法

• 批准号: 191645520
• 负责人: Privatdozentin Dr. Angelika Hausser
• 金额: --
• 依托单位: Institut für Zellbiologie und Immunologie (IZI)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/191645520?language=en
• 关键词: Protein; kinase; mediated; balance; between

Lipid metabolism, sorting and transport between different organelles are tightly regulated in mammalian cells, since lipid homeostasis is critical for maintaining the integrities of cellular membranes. At the Golgi complex the lipid composition determines the formation of transport vesicles, which are required to shuffle secretory proteins from the trans-Golgi network (TGN) to the cell membrane. Protein kinase D (PKD) has been shown to play an important role in this regulation: Active PKD is directly involved in the fission of transport vesicles at the TGN. Furthermore, it has a dual function for the ceramide transport from the endoplasmic reticulum (ER) to the TGN by regulating the activity of the ceramide transfer protein (CERT) in two opposite ways. PKD and CERT mutually regulate each other in a complex structure of interrelated feedback circuits, making this system an attractive target for a holistic modeling approach. Moreover, recent advances in experimental techniques have led to new insights about molecular interactions at the TGN, and regulation of secretion has not yet been taken into account in theoretical secretion models. The goal of this project is to increase our understanding about the role of PKD in the balance between lipid homeostasis and secretion. This will be achieved by a data- and knowledge-driven modeling approach based on chemical reaction kinetics, which will be accompanied by perturbation experiments that are used for model identification. We will particularly focus on statistical methods for parameter estimation and model selection, identifiability analysis, and systems-theoretic methods to investigate coupled feedback. The results of our project will be highly relevant for biotechnological applications: We may reveal targets for optimization of mammalian host cell lines used for therapeutic protein production, where regulation processes at the TGN have recently been identified as a bottleneck in the secretory pathways.

在哺乳动物细胞中，脂质代谢、不同细胞器之间的分选和运输受到严格的调节，因为脂质稳态对于维持细胞膜的完整性至关重要。在高尔基体复合体中，脂质组成决定了转运囊泡的形成，转运囊泡是将分泌蛋白从高尔基体网络（trans-Golgi network，TGN）转运到细胞膜所必需的。蛋白激酶D（PKD）已被证明在这种调节中发挥重要作用：活性PKD直接参与TGN运输囊泡的分裂。此外，它还通过两种相反的方式调节神经酰胺转运蛋白（CERT）的活性，对神经酰胺从内质网（ER）转运到TGN具有双重功能。PKD和CERT在相互关联的反馈电路的复杂结构中相互调节，使得该系统成为整体建模方法的有吸引力的目标。此外，实验技术的最新进展导致了对TGN分子相互作用的新见解，并且在理论分泌模型中尚未考虑分泌的调节。本项目的目的是增加我们对PKD在脂质稳态和分泌平衡中的作用的理解。这将通过基于化学反应动力学的数据和知识驱动的建模方法来实现，该方法将伴随着用于模型识别的扰动实验。我们将特别关注参数估计和模型选择的统计方法，可识别性分析，以及研究耦合反馈的系统理论方法。我们的项目的结果将是高度相关的生物技术应用：我们可能会发现用于治疗性蛋白质生产的哺乳动物宿主细胞系的优化目标，其中TGN的调节过程最近被确定为分泌途径的瓶颈。