The hydrophobic nature of a novel membrane interface regulates the enzyme activity of a voltage-sensing phosphatase
- Osaka University, Japan
- Teikyo University, Japan
- Osaka Medical College, Japan
Abstract
Voltage-sensing phosphatases (VSP) contain a voltage sensor domain (VSD) similar to that of voltage-gated ion channels but lack a pore-gate domain. A VSD in a VSP regulates the cytoplasmic catalytic region (CCR). However, the mechanisms by which the VSD couples to the CCR remain elusive. Here we report a membrane interface (named 'the hydrophobic spine'), which is essential for the coupling of the VSD and CCR. Our molecular dynamics simulations suggest that the hydrophobic spine of Ciona intestinalis VSP (Ci-VSP) provides a hinge-like motion for the CCR through the loose membrane association of the phosphatase domain. Electrophysiological experiments indicate that the voltage-dependent phosphatase activity of Ci-VSP depends on the hydrophobicity and presence of an aromatic ring in the hydrophobic spine. Analysis of conformational changes in the VSD and CCR suggests that the VSP has two states with distinct enzyme activities and that the second transition depends on the hydrophobic spine.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 4,5,6,7,8,9 and 10.
Article and author information
Author details
Funding
Core Research for Evolutional Science and Technology (JPMJCR14M3)
- Atsushi Nakagawa
- Yasushi Okamura
Ministry of Education, Culture, Sports, Science, and Technology (25253016)
- Yasushi Okamura
Japan Society for the Promotion of Science (15H05901)
- Yasushi Okamura
Japan Society for the Promotion of Science (JP15K18516)
- Akira Kawanabe
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were carried out following the guidelines of the Animal Research Committees of the Graduate School of Medicine of Osaka University.
Copyright
© 2018, Kawanabe et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The hydrophobic nature of a novel membrane interface regulates the enzyme activity of a voltage-sensing phosphatase
eLife 7:e41653.
https://doi.org/10.7554/eLife.41653
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