Membrane interactions of the globular domain and the hypervariable region of KRAS4b define its unique diffusion behavior
- Frederick National Laboratory for Cancer Research, United States
- Lawrence Livermore National Laboratory, United States
- University of California, San Francisco, United States
Abstract
The RAS proteins are GTP-dependent switches that regulate signaling pathways and are frequently mutated in cancer. RAS proteins concentrate in the plasma membrane via lipid-tethers and hypervariable side-chain interactions in distinct nano-domains. However, little is known about RAS membrane dynamics and the details of RAS activation of downstream signaling. Here we characterize RAS in live human and mouse cells using single molecule tracking methods and estimate RAS mobility parameters. KRAS4b exhibits confined mobility with three diffusive states distinct from the other RAS isoforms (KRAS4a, NRAS, and HRAS); and although most of the amino acid differences between RAS isoforms lie within the hypervariable region, the additional confinement of KRAS4b is largely determined by the protein's globular domain. To understand the altered mobility of an oncogenic KRAS4b we used complementary experimental and molecular dynamic simulation approaches to reveal a detailed mechanism.
Data availability
For the molecular dynamic simulations, trajectories and inputs have been provided on the webpage at https://bbs.llnl.gov/KRAS4b-simulation-data.html.For the images, we will access a suitable repository, and make the data freely available.
Article and author information
Author details
Felice C Lightstone
Funding
National Cancer Institute (NIH Contract HHSN261200800001E)
- De Chen
- Prabhakar R Gudla
- John Columbus
- Karen Worthy
- Megan Rigby
- Suman Mukhopadhyay
- Katie Powell
- William Burgan
- Vanessa Wall
- Dominic Esposito
- Dhirendra Simanshu
- Dwight V Nissley
- Thomas Turbyville
U.S. Department of Energy (Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-JRNL-771099-DRAFT)
- Yue Yang
- Felice C Lightstone
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Membrane interactions of the globular domain and the hypervariable region of KRAS4b define its unique diffusion behavior
eLife 9:e47654.
https://doi.org/10.7554/eLife.47654
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