Light-Regulated allosteric switch enables temporal and subcellular control of enzyme activity
Abstract
Engineered allosteric regulation of protein activity provides significant advantages for the development of robust and broadly applicable tools. However, the application of allosteric switches in optogenetics has been scarce and suffers from critical limitations. Here, we report an optogenetic approach that utilizes an engineered Light-Regulated (LightR) allosteric switch module to achieve tight spatiotemporal control of enzymatic activity. Using the tyrosine kinase Src as a model, we demonstrate efficient regulation of the kinase and identify temporally distinct signaling responses ranging from seconds to minutes. LightR-Src off-kinetics can be tuned by modulating the LightR photoconversion cycle. A fast cycling variant enables the stimulation of transient pulses and local regulation of activity in a selected region of a cell. The design of the LightR module ensures broad applicability of the tool, as we demonstrate by achieving light-mediated regulation of Abl and bRaf kinases as well as Cre recombinase.
Data availability
The raw mass spectrometry data and associated tables have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier: PXD018162. All data generated or analyzed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Institutes of Health (R21CA212907)
- Jordan Fauser
National Institutes of Health (CA238720)
- Forest M White
Chicago Biomedical Consortium
- Andrei V Karginov
Army Research Office (W911NF-17-1-0395)
- Denis Tsygankov
National Institutes of Health (R21CA159179)
- Andrei V Karginov
National Institutes of Health (R01GM118582)
- Andrei V Karginov
National Institutes of Health (R21CA223915)
- Jalees Rehman
- Andrei V Karginov
National Institutes of Health (HL007829-22)
- Mark Shaaya
- Jordan Fauser
- Martin Brennan
National Institutes of Health (P01 HL060678)
- Viswanathan Natarajan
- Jalees Rehman
- Andrei V Karginov
National Institutes of Health (CA210180)
- Forest M White
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Luis F Larrondo, Pontificia Universidad Católica de Chile, Chile
Publication history
- Received: July 2, 2020
- Accepted: September 22, 2020
- Accepted Manuscript published: September 23, 2020 (version 1)
- Accepted Manuscript updated: September 24, 2020 (version 2)
- Version of Record published: October 21, 2020 (version 3)
- Version of Record updated: November 11, 2020 (version 4)
Copyright
© 2020, Shaaya 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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Activation of G protein-coupled receptors (GPCRs) is an allosteric process. It involves conformational coupling between the orthosteric ligand binding site and the G protein binding site. Factors that bind at non-cognate ligand binding sites to alter the allosteric activation process are classified as allosteric modulators and represent a promising class of therapeutics with distinct modes of binding and action. For many receptors, how modulation of signaling is represented at the structural level is unclear. Here, we developed FRET sensors to quantify receptor modulation at each of the three structural domains of metabotropic glutamate receptor 2 (mGluR2). We identified the conformational fingerprint for several allosteric modulators in live cells. This approach enabled us to derive a receptor-centric representation of allosteric modulation and to correlate structural modulation to the standard signaling modulation metrics. Single-molecule FRET analysis revealed that a NAM increases the occupancy of one of the intermediate states while a PAM increases the occupancy of the active state. Moreover, we found that the effect of allosteric modulators on the receptor dynamics is complex and depend on the orthosteric ligand. Collectively, our findings provide a structural mechanism of allosteric modulation in mGluR2 and suggest possible strategies for design of future modulators.
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