Cryo-EM analyses reveal the common mechanism and diversification in the activation of RET by different ligands
- University of Texas Southwestern Medical Center, United States
Abstract
RET is a receptor tyrosine kinase (RTK) that plays essential roles in development and has been implicated in several human diseases. Different from most of RTKs, RET requires not only its cognate ligands but also co-receptors for activation, the mechanisms of which remain unclear due to lack of high-resolution structures of the ligand/co-receptor/receptor complexes. Here, we report cryo-EM structures of the extracellular region ternary complexes of GDF15/GFRAL/RET, GDNF/GFRα1/RET, NRTN/GFRα2/RET and ARTN/GFRα3/RET. These structures reveal that all the four ligand/co-receptor pairs, while using different atomic interactions, induce a specific dimerization mode of RET that is poised to bring the two kinase domains into close proximity for cross-phosphorylation. The NRTN/GFRα2/RET dimeric complex further pack into a tetrameric assembly, which is shown by our cell-based assays to regulate the endocytosis of RET. Our analyses therefore reveal both the common mechanism and diversification in the activation of RET by different ligands.
Data availability
Cryo-EM maps and the corresponding models of RET/co-receptors/ligands complexes have been deposited in EMDB and PDB under the accession codes EMD-20572/EMD-20573/EMD-20575/EMD-20576/EMD-20577/EMD-20578/EMD-20579/EMD-20580 and 6Q2J/6Q2N/6Q2O/6Q2R/6Q2S, respectively. All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 5 and Figure 5-Supplement 1.
Article and author information
Author details
Funding
Cancer Prevention and Research Institute of Texas (RR160082)
- Xiao-chen Bai
Welch Foundation (I-1944-20180324)
- Xiao-chen Bai
National Institutes of Health (GM088197)
- Xuewu Zhang
National Institutes of Health (R35GM130289)
- Xuewu Zhang
Welch Foundation (I-1702)
- Xuewu Zhang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Li 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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Cryo-EM analyses reveal the common mechanism and diversification in the activation of RET by different ligands
eLife 8:e47650.
https://doi.org/10.7554/eLife.47650
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