Zhang Xuejun C, Cao Can, Zhou Ye, Zhao Yan
National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China,
Protein Cell. 2015 Jan;6(1):12-7. doi: 10.1007/s13238-014-0106-4. Epub 2014 Oct 17.
G-protein coupled receptors (GPCRs) play essential roles in signal transduction from the environment into the cell. While many structural features have been elucidated in great detail, a common functional mechanism on how the ligand-binding signal is converted into a conformational change on the cytoplasmic face resulting in subsequent activation of downstream effectors remain to be established. Based on available structural and functional data of the activation process in class-A GPCRs, we propose here that a change in protonation status, together with proton transfer via conserved structural elements located in the transmembrane region, are the key elements essential for signal transduction across the membrane.
G蛋白偶联受体（GPCRs）在从细胞外环境到细胞内的信号转导中发挥着至关重要的作用。尽管许多结构特征已得到详细阐明，但关于配体结合信号如何转化为胞质面的构象变化从而导致下游效应器的后续激活这一常见功能机制仍有待确定。基于A类GPCRs激活过程中现有的结构和功能数据，我们在此提出，质子化状态的改变以及通过位于跨膜区域的保守结构元件进行的质子转移，是跨膜信号转导的关键要素。
