Clayton Gina M, Silverman William R, Heginbotham Lise, Morais-Cabral João H
Department of Molecular Biophysics and Biochemistry, Yale University, 260 Whitney Avenue, New Haven, CT 06520, USA.
Cell. 2004 Nov 24;119(5):615-27. doi: 10.1016/j.cell.2004.10.030.
Here we describe the initial functional characterization of a cyclic nucleotide regulated ion channel from the bacterium Mesorhizobium loti and present two structures of its cyclic nucleotide binding domain, with and without cAMP. The domains are organized as dimers with the interface formed by the linker regions that connect the nucleotide binding pocket to the pore domain. Together, structural and functional data suggest the domains form two dimers on the cytoplasmic face of the channel. We propose a model for gating in which ligand binding alters the structural relationship within a dimer, directly affecting the position of the adjacent transmembrane helices.
在此，我们描述了来自百脉根中生根瘤菌的一种环核苷酸调节离子通道的初步功能特性，并展示了其环核苷酸结合结构域在结合和未结合cAMP时的两种结构。这些结构域以二聚体形式组织，其界面由连接核苷酸结合口袋与孔道结构域的连接区域形成。结构和功能数据共同表明，这些结构域在通道的胞质面形成两个二聚体。我们提出了一种门控模型，其中配体结合改变了二聚体内的结构关系，直接影响相邻跨膜螺旋的位置。
