An expanded allosteric network in PTP1B by multitemperature crystallography, fragment screening, and covalent tethering
Abstract
Allostery is an inherent feature of proteins, but it remains challenging to reveal the mechanisms by which allosteric signals propagate. A clearer understanding of this intrinsic circuitry would afford new opportunities to modulate protein function. Here we have identified allosteric sites in protein tyrosine phosphatase 1B (PTP1B) by combining multiple-temperature X-ray crystallography experiments and structure determination from hundreds of individual small-molecule fragment soaks. New modeling approaches reveal 'hidden' low-occupancy conformational states for protein and ligands. Our results converge on allosteric sites that are conformationally coupled to the active-site WPD loop and are hotspots for fragment binding. Targeting one of these sites with covalently tethered molecules or mutations allosterically inhibits enzyme activity. Overall, this work demonstrates how the ensemble nature of macromolecular structure, revealed here by multitemperature crystallography, can elucidate allosteric mechanisms and open new doors for long-range control of protein function.
Data availability
Data have been deposited in PDB under the accession codes: 6B90, 6B8E, 6B8T, 6B8X, 6B8Z, 6BAI, 6B95, 5QDE, 5QDF, 5QDG, 5QDH, 5QDI, 5QDJ, 5QDK, 5QDL, 5QDM, 5QDN, 5QDO, 5QDP, 5QDQ, 5QDR, 5QDS, 5QDT, 5QDU, 5QDV, 5QDW, 5QDX, 5QDY, 5QDZ, 5QE0, 5QE1, 5QE2, 5QE3, 5QE4, 5QE5, 5QE6, 5QE7, 5QE8, 5QE9, 5QEA, 5QEB, 5QEC, 5QED, 5QEE, 5QEF, 5QEG, 5QEH, 5QEI, 5QEJ, 5QEK, 5QEL, 5QEM, 5QEN, 5QEO, 5QEP, 5QEQ, 5QER, 5QES, 5QET, 5QEU, 5QEV, 5QEW, 5QEX, 5QEY, 5QEZ, 5QF0, 5QF1, 5QF2, 5QF3, 5QF4, 5QF5, 5QF6, 5QF7, 5QF8, 5QF9, 5QFA, 5QFB, 5QFC, 5QFD, 5QFE, 5QFF, 5QFG, 5QFH, 5QFI, 5QFJ, 5QFK, 5QFL, 5QFM, 5QFN, 5QFO, 5QFP, 5QFQ, 5QFR, 5QFS, 5QFT, 5QFU, 5QFV, 5QFW, 5QFX, 5QFY, 5QFZ, 5QG0, 5QG1, 5QG2, 5QG3, 5QG4, 5QG5, 5QG6, 5QG7, 5QG8, 5QG9, 5QGA, 5QGB, 5QGC, 5QGD, 5QGE, 5QGF and further data available at https://zenodo.org/record/1044103
Article and author information
Author details
Funding
Kinship Foundation
- James S Fraser
National Cancer Institute (CA191018)
- James A Wells
National Cancer Institute ((F31 CA180378)
- T Justin Rettenmaier
National Institute of General Medical Sciences (GM123159)
- James S Fraser
National Institute of General Medical Sciences (GM124169)
- James S Fraser
National Institute of General Medical Sciences (GM124149)
- James S Fraser
Pew Charitable Trusts
- James S Fraser
David and Lucile Packard Foundation
- James S Fraser
National Institute of General Medical Sciences (GM110580)
- James S Fraser
National Science Foundation (STC-1231306)
- James S Fraser
University of California (LFR-17-476732)
- James S Fraser
Helen Hay Whitney Foundation
- Zachary B Hill
National Cancer Institute (K99CA203002)
- Zachary B Hill
A.P. Giannini Foundation (Postdoctoral Fellowship)
- Daniel A Keedy
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yibing Shan, DE Shaw Research, United States
Version history
- Received: March 1, 2018
- Accepted: June 4, 2018
- Accepted Manuscript published: June 7, 2018 (version 1)
- Version of Record published: July 10, 2018 (version 2)
Copyright
© 2018, Keedy 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.
Metrics
-
- 6,946
- views
-
- 1,128
- downloads
-
- 92
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Biochemistry and Chemical Biology
- Structural Biology and Molecular Biophysics
NADPH oxidases (NOX) are transmembrane proteins, widely spread in eukaryotes and prokaryotes, that produce reactive oxygen species (ROS). Eukaryotes use the ROS products for innate immune defense and signaling in critical (patho)physiological processes. Despite the recent structures of human NOX isoforms, the activation of electron transfer remains incompletely understood. SpNOX, a homolog from Streptococcus pneumoniae, can serves as a robust model for exploring electron transfers in the NOX family thanks to its constitutive activity. Crystal structures of SpNOX full-length and dehydrogenase (DH) domain constructs are revealed here. The isolated DH domain acts as a flavin reductase, and both constructs use either NADPH or NADH as substrate. Our findings suggest that hydride transfer from NAD(P)H to FAD is the rate-limiting step in electron transfer. We identify significance of F397 in nicotinamide access to flavin isoalloxazine and confirm flavin binding contributions from both DH and Transmembrane (TM) domains. Comparison with related enzymes suggests that distal access to heme may influence the final electron acceptor, while the relative position of DH and TM does not necessarily correlate with activity, contrary to previous suggestions. It rather suggests requirement of an internal rearrangement, within the DH domain, to switch from a resting to an active state. Thus, SpNOX appears to be a good model of active NOX2, which allows us to propose an explanation for NOX2’s requirement for activation.
-
- Cell Biology
- Structural Biology and Molecular Biophysics
Acetylation of α-tubulin at the lysine 40 residue (αK40) by αTAT1/MEC-17 acetyltransferase modulates microtubule properties and occurs in most eukaryotic cells. Previous literatures suggest that acetylated microtubules are more stable and damage resistant. αK40 acetylation is the only known microtubule luminal post-translational modification site. The luminal location suggests that the modification tunes the lateral interaction of protofilaments inside the microtubule. In this study, we examined the effect of tubulin acetylation on the doublet microtubule (DMT) in the cilia of Tetrahymena thermophila using a combination of cryo-electron microscopy, molecular dynamics, and mass spectrometry. We found that αK40 acetylation exerts a small-scale effect on the DMT structure and stability by influencing the lateral rotational angle. In addition, comparative mass spectrometry revealed a link between αK40 acetylation and phosphorylation in cilia.