Di Silvio Eva, Bonetti Daniela, Toto Angelo, Morrone Angela, Gianni Stefano
Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche 'A. Rossi Fanelli', Sapienza Università di Roma, P.le A. Moro 5, 00185 Rome, Italy.
Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche 'A. Rossi Fanelli', Sapienza Università di Roma, P.le A. Moro 5, 00185 Rome, Italy Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
Protein Eng Des Sel. 2014 Aug;27(8):249-53. doi: 10.1093/protein/gzu022. Epub 2014 Jun 13.
Many biological processes are regulated by the interaction between protein domains and their corresponding binding partners. The PDZ domain is one of the most common protein-protein interaction modules in mammalian cells, whose role is to bind C-terminal sequences of specific targets. The second PDZ domain from the Protein Tyrosine Phosphatase-BL (PDZ2) binds to the C-terminal of Adenomatous Polyposis Coli protein (APC), one of the major tumor suppressor whose task is to regulate cell adhesion and proliferation. Here, we present a detailed kinetics analysis of the interaction between PDZ2 domain and a peptide mimicking the PDZ binding motif of APC. By analyzing data obtained at different experimental conditions, we propose a plausible mechanism for binding. Furthermore, a comparison between the dissociation rate constant measured by different methodologies allow us to identify an additional kinetic step, which is likely to arise from a conformational change of PDZ2 occurring after binding. The data are discussed on the light of previous work on PDZ domains.
许多生物过程是由蛋白质结构域与其相应结合伴侣之间的相互作用来调节的。PDZ结构域是哺乳动物细胞中最常见的蛋白质-蛋白质相互作用模块之一，其作用是结合特定靶标的C末端序列。蛋白酪氨酸磷酸酶-BL（PDZ2）的第二个PDZ结构域与腺瘤性息肉病大肠杆菌蛋白（APC）的C末端结合，APC是主要的肿瘤抑制因子之一，其任务是调节细胞黏附和增殖。在此，我们对PDZ2结构域与模拟APC的PDZ结合基序的肽之间的相互作用进行了详细的动力学分析。通过分析在不同实验条件下获得的数据，我们提出了一种合理的结合机制。此外，通过比较不同方法测得的解离速率常数，我们确定了一个额外的动力学步骤，这可能是由于结合后PDZ2发生构象变化而产生的。我们根据之前关于PDZ结构域的研究对这些数据进行了讨论。
