Fig. 3
From: Cryo-EM structure of the polycystic kidney disease-like channel PKD2L1
Conformational changes of the VSDs modeled in PKD2L1. a PKD2L1 (green) and PKD2 (gray) both harbor two lysines, K452 and K455 (resp. K572 and K575 in PKD2) in S4, which increases their voltage sensitivity. The two lysines are potentially stabilized by D390 from S3, Y107 from S1, and Y366 from S2 (resp. D511, Y227, and Y487 in PKD2). b Cytosolic view of structural comparison of PKD2L1 (colored as in Fig. 1) and its homologous closed-state model, excluding polycystin domains for the ease of visualization. The whole structure of PKD2L1 displays a clockwise rotation relative to its closed state as viewed from the intracellular side. The red full arrows indicate overall shifts of each protomer from the closed to open state. c One protomer from panel b viewed from the extracellular side; only six transmembrane helices of this protomer are shown. The red dotted arrows indicate the rotation of specific regions. d Dissection of the conformational shifts of the VSD segments relative to the pore domain. The open-state cryo-EM PKD2L1 structure and the closed-state PKD2L1 model are superimposed overall. Adjacent helices are shown in each panel as the reference to indicate the orientation of the structures. The respective residue names and numbers in PKD2 are shown in gray within parentheses throughout this study when applicable (esp. Figs. 3–5)
