Identification of the Conformational transition pathway in PIP2 Opening Kir Channels

Authors

Junwei Li, Hebei University of Technology
Shouqin Lü, Chinese Academy of Sciences
Yuzhi Liu, Shijiazhuang Tiedao University
Chunli Pang, Hebei University of Technology
Yafei Chen, Hebei University of Technology
Suhua Zhang, Hebei University of Technology
Hui Yu, Hebei University of Technology
Mian Long, Chinese Academy of Sciences
Hailin Zhang, Hebei Medical University
Diomedes E. Logothetis, Virginia Commonwealth University
Yong Zhan, Hebei University of TechnologyFollow
Hailong An, Hebei University of TechnologyFollow

Document Type

Article

Original Publication Date

2015

Journal/Book/Conference Title

Scientific Reports

Volume

5

DOI of Original Publication

10.1038/srep11289

Comments

Originally published at http://dx.doi.org/10.1038/srep11289

Date of Submission

November 2015

Abstract

The gating of Kir channels depends critically on phosphatidylinositol 4,5-bisphosphate (PIP2), but the detailed mechanism by which PIP2regulates Kir channels remains obscure. Here, we performed a series of Targeted molecular dynamics simulations on the full-length Kir2.1 channel and, for the first time, were able to achieve the transition from the closed to the open state. Our data show that with the upward motion of the cytoplasmic domain (CTD) the structure of the C-Linker changes from a loop to a helix. The twisting of the C-linker triggers the rotation of the CTD, which induces a small downward movement of the CTD and an upward motion of the slide helix toward the membrane that pulls the inner helix gate open. At the same time, the rotation of the CTD breaks the interaction between the CD- and G-loops thus releasing the G-loop. The G-loop then bounces away from the CD-loop, which leads to the opening of the G-loop gate and the full opening of the pore. We identified a series of interaction networks, between the N-terminus, CD loop, C linker and G loop one by one, which exquisitely regulates the global conformational changes during the opening of Kir channels by PIP2.

Rights

Li, J. et al. Identification of the Conformational transition pathway in PIP2 Opening Kir Channels. Sci. Rep. 5, 11289; doi: 10.1038/srep11289 (2015). This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

Is Part Of

VCU Physiology and Biophysics Publications