Regulatory role of the extreme C‐terminal end of the S6 inner helix in C‐terminal‐truncated Kv1.2 channel activation |
| |
| Authors: | Li‐Li Zhao Zhi Qi Xian‐En Zhang Li‐Jun Bi Gang Jin |
| |
| Affiliation: | 1. National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Rd, Beijing 100101, China;2. National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and PreventionState Key Laboratory for Infectious Disease Prevention and Control, Beijing 102206, China;3. State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Rd, Beijing 100101, China;4. State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China |
| |
| Abstract: | The transmembrane part of the S6 inner helix of the Kv1.2 potassium channel is a pivotal part in sustaining channel activity. However, the role of its extreme C‐terminal end, which is located on the cytoplasmic side of the channel, is largely unknown. Here, we investigated the role of the extreme C‐terminal end of the S6 inner helix (the HRET region) by constructing a series of C‐terminal‐truncated mutations related to this region in the C‐terminal‐truncated Kv1.2 channel. Mutations on Thr421 or Glu420 significantly altered the activation of the truncated channel. Mutations on Arg419 demonstrated that neutral or basic, but not acidic amino acid, is essential at the position for the truncated channel activation, and no functional channel was observed when the channel was truncated from His418. Hence, our results indicate that the extreme C‐terminal end of the S6 inner helix plays an important regulatory role in the activation of the C‐terminal‐truncated Kv1.2 channel. |
| |
| Keywords: | activation Kv1.2 channel patch‐clamp surface expression S6 inner helix |
|
|
