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Kim YJ, Tohyama S, Nagashima T, Nagase M, Hida Y, Hamada S, Watabe AM, Ohtsuka T. A light-controlled phospholipase C for imaging of lipid dynamics and controlling neural plasticity. Cell Chem Biol 2024; 31:1336-1348.e7. [PMID: 38582083 DOI: 10.1016/j.chembiol.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 02/05/2024] [Accepted: 03/12/2024] [Indexed: 04/08/2024]
Abstract
Phospholipase C (PLC) is a key enzyme that regulates physiological processes via lipid and calcium signaling. Despite advances in protein engineering, no tools are available for direct PLC control. Here, we developed a novel optogenetic tool, light-controlled PLCβ (opto-PLCβ). Opto-PLCβ uses a light-induced dimer module, which directs an engineered PLC to the plasma membrane in a light-dependent manner. Our design includes an autoinhibitory capacity, ensuring stringent control over PLC activity. Opto-PLCβ triggers reversible calcium responses and lipid dynamics in a restricted region, allowing precise spatiotemporal control of PLC signaling. Using our system, we discovered that phospholipase D-mediated phosphatidic acid contributes to diacylglycerol clearance on the plasma membrane. Moreover, we extended its applicability in vivo, demonstrating that opto-PLCβ can enhance amygdala synaptic plasticity and associative fear learning in mice. Thus, opto-PLCβ offers precise spatiotemporal control, enabling comprehensive investigation of PLC-mediated signaling pathways, lipid dynamics, and their physiological consequences in vivo.
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Affiliation(s)
- Yeon-Jeong Kim
- Department of Biochemistry, Graduate School of Medicine, Faculty of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan
| | - Suguru Tohyama
- Institute of Clinical Medicine and Research, Research Center for Medical Sciences, The Jikei University School of Medicine, Chiba, Japan
| | - Takashi Nagashima
- Institute of Clinical Medicine and Research, Research Center for Medical Sciences, The Jikei University School of Medicine, Chiba, Japan
| | - Masashi Nagase
- Institute of Clinical Medicine and Research, Research Center for Medical Sciences, The Jikei University School of Medicine, Chiba, Japan
| | - Yamato Hida
- Department of Biochemistry, Graduate School of Medicine, Faculty of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan
| | - Shun Hamada
- Department of Biochemistry, Graduate School of Medicine, Faculty of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan
| | - Ayako M Watabe
- Institute of Clinical Medicine and Research, Research Center for Medical Sciences, The Jikei University School of Medicine, Chiba, Japan.
| | - Toshihisa Ohtsuka
- Department of Biochemistry, Graduate School of Medicine, Faculty of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan.
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2
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Ubeysinghe S, Kankanamge D, Thotamune W, Wijayaratna D, Mohan TM, Karunarathne A. Spatiotemporal Optical Control of Gαq-PLCβ Interactions. ACS Synth Biol 2024; 13:242-258. [PMID: 38092428 DOI: 10.1021/acssynbio.3c00490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2023]
Abstract
Cells experience time-varying and spatially heterogeneous chemokine signals in vivo, activating cell surface proteins including G protein-coupled receptors (GPCRs). The Gαq pathway activation by GPCRs is a major signaling axis with broad physiological and pathological significance. Compared with other Gα members, GαqGTP activates many crucial effectors, including PLCβ (Phospholipase Cβ) and Rho GEFs (Rho guanine nucleotide exchange factors). PLCβ regulates many key processes, such as hematopoiesis, synaptogenesis, and cell cycle, and is therefore implicated in terminal-debilitating diseases, including cancer, epilepsy, Huntington's Disease, and Alzheimer's Disease. However, due to a lack of genetic and pharmacological tools, examining how the dynamic regulation of PLCβ signaling controls cellular physiology has been difficult. Since activated PLCβ induces several abrupt cellular changes, including cell morphology, examining how the other pathways downstream of Gq-GPCRs contribute to the overall signaling has also been difficult. Here we show the engineering, validation, and application of a highly selective and efficient optogenetic inhibitor (Opto-dHTH) to completely disrupt GαqGTP-PLCβ interactions reversibly in user-defined cellular-subcellular regions on optical command. Using this newly gained PLCβ signaling control, our data indicate that the molecular competition between RhoGEFs and PLCβ for GαqGTP determines the potency of Gq-GPCR-governed directional cell migration.
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Affiliation(s)
- Sithurandi Ubeysinghe
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Dinesh Kankanamge
- Pain Center, Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Waruna Thotamune
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Dhanushan Wijayaratna
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Thomas M Mohan
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Ajith Karunarathne
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
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3
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Arshi SA, Chauhan M, Sharma A. Disruption of the FMN-A524 interaction cascade and Glu513-induced collapse of the hydrophobic barrier promotes light-induced Jα-helix unfolding in AsLOV2. Biophys J 2023; 122:4670-4685. [PMID: 37978801 PMCID: PMC10754690 DOI: 10.1016/j.bpj.2023.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 10/10/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
The C-terminal Jα-helix of the Avena sativa's Light Oxygen and Voltage (AsLOV2) protein, unfolds on exposure to blue light. This characteristic seeks relevance in applications related to engineering novel biological photoswitches. Using molecular dynamics simulations and the Markov state modeling (MSM) approach we provide the mechanism that explains the stepwise unfolding of the Jα-helix. The unfolding was resolved into seven steps represented by the structurally distinguishable states distributed over the initiation and the post initiation phases. Whereas, the initiation phase occurs due to the collapse of the interaction cascade FMN-Q513-N492-L480-W491-Q479-V520-A524, the onset of the post initiation phase is marked by breaking of the hydrophobic interactions between the Jα-helix and the Iβ-strand. This study indicates that the displacement of N492 out of the FMN binding pocket, not necessarily requiring Q513, is essential for the initiation of the Jα-helix unfolding. Rather, the structural reorientation of Q513 activates the protein to cross the hydrophobic barrier and enter the post initiation phase. Similarly, the structural deviations in N482, rather than its integral role in unfolding, could enhance the unfolding rates. Furthermore, the MSM studies on the wild-type and the Q513 mutant, provide the spatiotemporal roadmap that lay out the possible pathways of structural transition between the dark and the light states of the protein. Overall, the study provides insights useful to enhance the performance of AsLOV2-based photoswitches.
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Affiliation(s)
- Syeda Amna Arshi
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Manisha Chauhan
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Amit Sharma
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India.
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Alapin JM, Mohamed MS, Shrestha P, Khaled HG, Vorabyeva AG, Bowling HL, Oliveira MM, Klann E. Opto4E-BP, an optogenetic tool for inducible, reversible, and cell type-specific inhibition of translation initiation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.30.554643. [PMID: 37693507 PMCID: PMC10491233 DOI: 10.1101/2023.08.30.554643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The protein kinase mechanistic target of rapamycin complex 1 (mTORC1) is one of the primary triggers for initiating cap-dependent translation. Amongst its functions, mTORC1 phosphorylates eIF4E-binding proteins (4E-BPs), which prevents them from binding to eIF4E and thereby enables translation initiation. mTORC1 signaling is required for multiple forms of protein synthesis-dependent synaptic plasticity and various forms of long-term memory (LTM), including associative threat memory. However, the approaches used thus far to target mTORC1 and its effectors, such as pharmacological inhibitors or genetic knockouts, lack fine spatial and temporal control. The development of a conditional and inducible eIF4E knockdown mouse line partially solved the issue of spatial control, but still lacked optimal temporal control to study memory consolidation. Here, we have designed a novel optogenetic tool (Opto4E-BP) for cell type-specific, light-dependent regulation of eIF4E in the brain. We show that light-activation of Opto4E-BP decreases protein synthesis in HEK cells and primary mouse neurons. In situ , light-activation of Opto4E-BP in excitatory neurons decreased protein synthesis in acute amygdala slices. Finally, light activation of Opto4E-BP in principal excitatory neurons in the lateral amygdala (LA) of mice after training blocked the consolidation of LTM. The development of this novel optogenetic tool to modulate eIF4E-dependent translation with spatiotemporal precision will permit future studies to unravel the complex relationship between protein synthesis and the consolidation of LTM.
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5
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Ubeysinghe S, Kankanamge D, Thotamune W, Wijayaratna D, Mohan TM, Karunarathne A. Spatiotemporal optical control of Gαq-PLCβ interactions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552801. [PMID: 37609229 PMCID: PMC10441412 DOI: 10.1101/2023.08.10.552801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Cells experience time-varying and spatially heterogeneous chemokine signals in vivo, activating cell surface proteins, including G protein-coupled receptors (GPCRs). The Gαq pathway activation by GPCRs is a major signaling axis with a broad physiological and pathological significance. Compared to other Gα members, GαqGTP activates many crucial effectors, including PLCβ (Phospholipase Cβ) and Rho GEFs (Rho guanine nucleotide exchange factors). PLCβ regulates many key processes, such as hematopoiesis, synaptogenesis, and cell cycle, and is therefore implicated in terminal - debilitating diseases, including cancer, epilepsy, Huntington's Disease, and Alzheimer's Disease. However, due to a lack of genetic and pharmacological tools, examining how the dynamic regulation of PLCβ signaling controls cellular physiology has been difficult. Since activated PLCβ induces several abrupt cellular changes, including cell morphology, examining how the other pathways downstream of Gq-GPCRs contribute to the overall signaling has also been difficult. Here we show the engineering, validation, and application of a highly selective and efficient optogenetic inhibitor (Opto-dHTH) to completely disrupt GαqGTP-PLCβ interactions reversibly in user-defined cellular-subcellular regions on optical command. Using this newly gained PLCβ signaling control, our data indicate that the molecular competition between RhoGEFs and PLCβ for GαqGTP determines the potency of Gq-GPCR-governed directional cell migration.
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6
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Shen J, Geng L, Li X, Emery C, Kroning K, Shingles G, Lee K, Heyden M, Li P, Wang W. A general method for chemogenetic control of peptide function. Nat Methods 2023; 20:112-122. [PMID: 36481965 PMCID: PMC10069916 DOI: 10.1038/s41592-022-01697-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 10/21/2022] [Indexed: 12/13/2022]
Abstract
Natural or engineered peptides serve important biological functions. A general approach to achieve chemical-dependent activation of short peptides will be valuable for spatial and temporal control of cellular processes. Here we present a pair of chemically activated protein domains (CAPs) for controlling the accessibility of both the N- and C-terminal portion of a peptide. CAPs were developed through directed evolution of an FK506-binding protein. By fusing a peptide to one or both CAPs, the function of the peptide is blocked until a small molecule displaces them from the FK506-binding protein ligand-binding site. We demonstrate that CAPs are generally applicable to a range of short peptides, including a protease cleavage site, a dimerization-inducing heptapeptide, a nuclear localization signal peptide, and an opioid peptide, with a chemical dependence up to 156-fold. We show that the CAPs system can be utilized in cell cultures and multiple organs in living animals.
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Affiliation(s)
- Jiaqi Shen
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Lequn Geng
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Xingyu Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Biologic and Materials Sciences & Prosthodontics, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Catherine Emery
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Biologic and Materials Sciences & Prosthodontics, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Kayla Kroning
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Gwendolyn Shingles
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Kerry Lee
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Matthias Heyden
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
| | - Peng Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Biologic and Materials Sciences & Prosthodontics, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA.
| | - Wenjing Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA.
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7
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Zhou G, Wan WW, Wang W. Modular Peroxidase-Based Reporters for Detecting Protease Activity and Protein Interactions with Temporal Gating. J Am Chem Soc 2022; 144:22933-22940. [PMID: 36511757 PMCID: PMC10026560 DOI: 10.1021/jacs.2c08280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Enzymatic reporters have been widely applied to study various biological processes because they can amplify signal through enzymatic reactions and provide good sensitivity. However, there is still a need for modular motifs for designing a series of enzymatic reporters. Here, we report a modular peroxidase-based motif, named CLAPon, that features acid-base coil-caged enhanced ascorbate peroxidase (APEX). We demonstrate the modularity of CLAPon by designing a series of reporters for detecting protease activity and protein-protein interactions (PPIs). CLAPon for protease activity showed a 390-fold fluorescent signal increase upon tobacco etch virus protease cleavage. CLAPon for PPI detection (PPI-CLAPon) has two variants, PPI-CLAPon1.0 and 1.1. PPI-CLAPon1.0 showed a signal-to-noise ratio (SNR) of up to 107 for high-affinity PPI pairs and enabled imaging with sub-cellular spatial resolution. However, the more sensitive PPI-CLAPon1.1 is required for detecting low-affinity PPI pairs. PPI-CLAPon1.0 was further engineered to a reporter with light-dependent temporal gating, called LiPPI-CLAPon1.0, which can detect a 3-min calcium-dependent PPI with an SNR of 17. LiPPI-CLAPon enables PPI detection within a specific time window with rapid APEX activation and diverse readout. Lastly, PPI-CLAPon1.0 was designed to have chemical gating, providing more versatility to complement the LiPPI-CLAPon. These CLAPon-based reporter designs can be broadly applied to study various signaling processes that involve protease activity and PPIs and provide a versatile platform to design various genetically encoded reporters.
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Affiliation(s)
- Guanwei Zhou
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Wei Wei Wan
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Wenjing Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Corresponding Author: Wenjing Wang,
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8
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Optogenetic and Chemical Induction Systems for Regulation of Transgene Expression in Plants: Use in Basic and Applied Research. Int J Mol Sci 2022; 23:ijms23031737. [PMID: 35163658 PMCID: PMC8835832 DOI: 10.3390/ijms23031737] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/27/2022] [Accepted: 01/29/2022] [Indexed: 02/01/2023] Open
Abstract
Continuous and ubiquitous expression of foreign genes sometimes results in harmful effects on the growth, development and metabolic activities of plants. Tissue-specific promoters help to overcome this disadvantage, but do not allow one to precisely control transgene expression over time. Thus, inducible transgene expression systems have obvious benefits. In plants, transcriptional regulation is usually driven by chemical agents under the control of chemically-inducible promoters. These systems are diverse, but usually contain two elements, the chimeric transcription factor and the reporter gene. The commonly used chemically-induced expression systems are tetracycline-, steroid-, insecticide-, copper-, and ethanol-regulated. Unlike chemical-inducible systems, optogenetic tools enable spatiotemporal, quantitative and reversible control over transgene expression with light, overcoming limitations of chemically-inducible systems. This review updates and summarizes optogenetic and chemical induction methods of transgene expression used in basic plant research and discusses their potential in field applications.
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9
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Lindner F, Diepold A. Optogenetics in bacteria - applications and opportunities. FEMS Microbiol Rev 2021; 46:6427354. [PMID: 34791201 PMCID: PMC8892541 DOI: 10.1093/femsre/fuab055] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/11/2021] [Indexed: 12/12/2022] Open
Abstract
Optogenetics holds the promise of controlling biological processes with superb temporal and spatial resolution at minimal perturbation. Although many of the light-reactive proteins used in optogenetic systems are derived from prokaryotes, applications were largely limited to eukaryotes for a long time. In recent years, however, an increasing number of microbiologists use optogenetics as a powerful new tool to study and control key aspects of bacterial biology in a fast and often reversible manner. After a brief discussion of optogenetic principles, this review provides an overview of the rapidly growing number of optogenetic applications in bacteria, with a particular focus on studies venturing beyond transcriptional control. To guide future experiments, we highlight helpful tools, provide considerations for successful application of optogenetics in bacterial systems, and identify particular opportunities and challenges that arise when applying these approaches in bacteria.
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Affiliation(s)
- Florian Lindner
- Max-Planck-Institute for Terrestrial Microbiology, Department of Ecophysiology, Karl-von-Frisch-Str. 10, 35043 Marburg, Germany
| | - Andreas Diepold
- Max-Planck-Institute for Terrestrial Microbiology, Department of Ecophysiology, Karl-von-Frisch-Str. 10, 35043 Marburg, Germany.,SYNMIKRO, LOEWE Center for Synthetic Microbiology, Marburg, Germany
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10
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Geng L, Shen J, Wang W. Circularly permuted AsLOV2 as an optogenetic module for engineering photoswitchable peptides. Chem Commun (Camb) 2021; 57:8051-8054. [PMID: 34291777 DOI: 10.1039/d1cc02643g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We re-engineered a commonly-used light-sensing protein, AsLOV2, using a circular permutation strategy to allow photoswitchable control of the C-terminus of a peptide. We demonstrate that the circularly permuted AsLOV2 can be used on its own or together with the original AsLOV2 for enhanced caging. In summary, circularly permuted AsLOV2 could expand the engineering capabilities of optogenetic tools.
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Affiliation(s)
- Lequn Geng
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA. and Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Jiaqi Shen
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA. and Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Wenjing Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA. and Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
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11
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Andrikopoulos PC, Chaudhari AS, Liu Y, Konold PE, Kennis JTM, Schneider B, Fuertes G. QM calculations predict the energetics and infrared spectra of transient glutamine isomers in LOV photoreceptors. Phys Chem Chem Phys 2021; 23:13934-13950. [PMID: 34142688 PMCID: PMC8246142 DOI: 10.1039/d1cp00447f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 06/04/2021] [Indexed: 11/21/2022]
Abstract
Photosensory receptors containing the flavin-binding light-oxygen-voltage (LOV) domain are modular proteins that fulfil a variety of biological functions ranging from gene expression to phototropism. The LOV photocycle is initiated by blue-light and involves a cascade of intermediate species, including an electronically excited triplet state, that leads to covalent bond formation between the flavin mononucleotide (FMN) chromophore and a nearby cysteine residue. Subsequent conformational changes in the polypeptide chain arise due to the remodelling of the hydrogen bond network in the cofactor binding pocket, whereby a conserved glutamine residue plays a key role in coupling FMN photochemistry with LOV photobiology. Although the dark-to-light transition of LOV photosensors has been previously addressed by spectroscopy and computational approaches, the mechanistic basis of the underlying reactions is still not well understood. Here we present a detailed computational study of three distinct LOV domains: EL222 from Erythrobacter litoralis, AsLOV2 from the second LOV domain of Avena sativa phototropin 1, and RsLOV from Rhodobacter sphaeroides LOV protein. Extended protein-chromophore models containing all known crucial residues involved in the initial steps (femtosecond-to-microsecond) of the photocycle were employed. Energies and rotational barriers were calculated for possible rotamers and tautomers of the critical glutamine side chain, which allowed us to postulate the most energetically favoured glutamine orientation for each LOV domain along the assumed reaction path. In turn, for each evolving species, infrared difference spectra were constructed and compared to experimental EL222 and AsLOV2 transient infrared spectra, the former from original work presented here and the latter from the literature. The good agreement between theory and experiment permitted the assignment of the majority of observed bands, notably the ∼1635 cm-1 transient of the adduct state to the carbonyl of the glutamine side chain after rotation. Moreover, both the energetic and spectroscopic approaches converge in suggesting a facile glutamine flip at the adduct intermediate for EL222 and more so for AsLOV2, while for RsLOV the glutamine keeps its initial configuration. Additionally, the computed infrared shifts of the glutamine and interacting residues could guide experimental research addressing early events of signal transduction in LOV proteins.
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Affiliation(s)
- Prokopis C Andrikopoulos
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Aditya S Chaudhari
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Yingliang Liu
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Patrick E Konold
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - John T M Kennis
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Bohdan Schneider
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Gustavo Fuertes
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
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12
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Forlani G, Di Ventura B. A light way for nuclear cell biologists. J Biochem 2021; 169:273-286. [PMID: 33245128 PMCID: PMC8053400 DOI: 10.1093/jb/mvaa139] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 11/12/2020] [Indexed: 12/11/2022] Open
Abstract
The nucleus is a very complex organelle present in eukaryotic cells. Having the crucial task to safeguard, organize and manage the genetic information, it must tightly control its molecular constituents, its shape and its internal architecture at any given time. Despite our vast knowledge of nuclear cell biology, much is yet to be unravelled. For instance, only recently we came to appreciate the existence of a dynamic nuclear cytoskeleton made of actin filaments that regulates processes such as gene expression, DNA repair and nuclear expansion. This suggests further exciting discoveries ahead of us. Modern cell biologists embrace a new methodology relying on precise perturbations of cellular processes that require a reversible, highly spatially confinable, rapid, inexpensive and tunEable external stimulus: light. In this review, we discuss how optogenetics, the state-of-the-art technology that uses genetically encoded light-sensitive proteins to steer biological processes, can be adopted to specifically investigate nuclear cell biology.
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Affiliation(s)
- Giada Forlani
- Spemann Graduate School of Biology and Medicine (SGBM)
- Centers for Biological Signalling Studies BIOSS and CIBSS
- Faculty of Biology, Institute of Biology II, Albert Ludwigs University of Freiburg, Freiburg, Germany
| | - Barbara Di Ventura
- Centers for Biological Signalling Studies BIOSS and CIBSS
- Faculty of Biology, Institute of Biology II, Albert Ludwigs University of Freiburg, Freiburg, Germany
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13
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Iuliano JN, Collado JT, Gil AA, Ravindran PT, Lukacs A, Shin S, Woroniecka HA, Adamczyk K, Aramini JM, Edupuganti UR, Hall CR, Greetham GM, Sazanovich IV, Clark IP, Daryaee T, Toettcher JE, French JB, Gardner KH, Simmerling CL, Meech SR, Tonge PJ. Unraveling the Mechanism of a LOV Domain Optogenetic Sensor: A Glutamine Lever Induces Unfolding of the Jα Helix. ACS Chem Biol 2020; 15:2752-2765. [PMID: 32880430 DOI: 10.1021/acschembio.0c00543] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Light-activated protein domains provide a convenient, modular, and genetically encodable sensor for optogenetics and optobiology. Although these domains have now been deployed in numerous systems, the precise mechanism of photoactivation and the accompanying structural dynamics that modulate output domain activity remain to be fully elucidated. In the C-terminal light-oxygen-voltage (LOV) domain of plant phototropins (LOV2), blue light activation leads to formation of an adduct between a conserved Cys residue and the embedded FMN chromophore, rotation of a conserved Gln (Q513), and unfolding of a helix (Jα-helix) which is coupled to the output domain. In the present work, we focus on the allosteric pathways leading to Jα helix unfolding in Avena sativa LOV2 (AsLOV2) using an interdisciplinary approach involving molecular dynamics simulations extending to 7 μs, time-resolved infrared spectroscopy, solution NMR spectroscopy, and in-cell optogenetic experiments. In the dark state, the side chain of N414 is hydrogen bonded to the backbone N-H of Q513. The simulations predict a lever-like motion of Q513 after Cys adduct formation resulting in a loss of the interaction between the side chain of N414 and the backbone C═O of Q513, and formation of a transient hydrogen bond between the Q513 and N414 side chains. The central role of N414 in signal transduction was evaluated by site-directed mutagenesis supporting a direct link between Jα helix unfolding dynamics and the cellular function of the Zdk2-AsLOV2 optogenetic construct. Through this multifaceted approach, we show that Q513 and N414 are critical mediators of protein structural dynamics, linking the ultrafast (sub-ps) excitation of the FMN chromophore to the microsecond conformational changes that result in photoreceptor activation and biological function.
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Affiliation(s)
- James N. Iuliano
- Department of Chemistry, Stony Brook University, New York, 11794, United States
| | | | - Agnieszka A. Gil
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Pavithran T. Ravindran
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Andras Lukacs
- School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
- Department of Biophysics, Medical School, University of Pecs, Szigeti út 12, 7624 Pecs, Hungary
| | - SeungYoun Shin
- Department of Chemistry, Stony Brook University, New York, 11794, United States
| | | | - Katrin Adamczyk
- School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - James M. Aramini
- Structural Biology Initiative, CUNY Advanced Science Research Center, 85 St. Nicholas Terrace, New York, New York 10031, United States
| | - Uthama R. Edupuganti
- Structural Biology Initiative, CUNY Advanced Science Research Center, 85 St. Nicholas Terrace, New York, New York 10031, United States
- Ph.D. Program in Biochemistry, CUNY Graduate Center, New York, New York, United States
| | - Christopher R. Hall
- School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Gregory M. Greetham
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, OX11 0QX, United Kingdom
| | - Igor V. Sazanovich
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, OX11 0QX, United Kingdom
| | - Ian P. Clark
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, OX11 0QX, United Kingdom
| | - Taraneh Daryaee
- Department of Chemistry, Stony Brook University, New York, 11794, United States
| | - Jared E. Toettcher
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Jarrod B. French
- Department of Chemistry, Stony Brook University, New York, 11794, United States
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Kevin H. Gardner
- Structural Biology Initiative, CUNY Advanced Science Research Center, 85 St. Nicholas Terrace, New York, New York 10031, United States
- Ph.D. Programs in Biochemistry, Biology, and Chemistry, CUNY Graduate Center, New York, New York, United States
- Department of Chemistry and Biochemistry, City College of New York, New York, New York, United States
| | | | - Stephen R. Meech
- School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Peter J. Tonge
- Department of Chemistry, Stony Brook University, New York, 11794, United States
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14
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Carrasco-López C, Zhao EM, Gil AA, Alam N, Toettcher JE, Avalos JL. Development of light-responsive protein binding in the monobody non-immunoglobulin scaffold. Nat Commun 2020; 11:4045. [PMID: 32792484 PMCID: PMC7427095 DOI: 10.1038/s41467-020-17837-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 07/13/2020] [Indexed: 12/24/2022] Open
Abstract
Monobodies are synthetic non-immunoglobulin customizable protein binders invaluable to basic and applied research, and of considerable potential as future therapeutics and diagnostic tools. The ability to reversibly control their binding activity to their targets on demand would significantly expand their applications in biotechnology, medicine, and research. Here we present, as proof-of-principle, the development of a light-controlled monobody (OptoMB) that works in vitro and in cells and whose affinity for its SH2-domain target exhibits a 330-fold shift in binding affinity upon illumination. We demonstrate that our αSH2-OptoMB can be used to purify SH2-tagged proteins directly from crude E. coli extract, achieving 99.8% purity and over 40% yield in a single purification step. By virtue of their ability to be designed to bind any protein of interest, OptoMBs have the potential to find new powerful applications as light-switchable binders of untagged proteins with the temporal and spatial precision afforded by light.
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Affiliation(s)
- César Carrasco-López
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Evan M Zhao
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Agnieszka A Gil
- Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA
| | - Nathan Alam
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Jared E Toettcher
- Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA.
| | - José L Avalos
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA.
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ, 08544, USA.
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15
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Optogenetic Control of Spine-Head JNK Reveals a Role in Dendritic Spine Regression. eNeuro 2020; 7:ENEURO.0303-19.2019. [PMID: 31937523 PMCID: PMC7053173 DOI: 10.1523/eneuro.0303-19.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 12/18/2019] [Accepted: 12/19/2019] [Indexed: 12/27/2022] Open
Abstract
In this study, we use an optogenetic inhibitor of c-Jun NH2-terminal kinase (JNK) in dendritic spine sub-compartments of rat hippocampal neurons. We show that JNK inhibition exerts rapid (within seconds) reorganization of actin in the spine-head. Using real-time Förster resonance energy transfer (FRET) to measure JNK activity, we find that either excitotoxic insult (NMDA) or endocrine stress (corticosterone), activate spine-head JNK causing internalization of AMPARs and spine retraction. Both events are prevented upon optogenetic inhibition of JNK, and rescued by JNK inhibition even 2 h after insult. Moreover, we identify that the fast-acting anti-depressant ketamine reduces JNK activity in hippocampal neurons suggesting that JNK inhibition may be a downstream mediator of its anti-depressant effect. In conclusion, we show that JNK activation plays a role in triggering spine elimination by NMDA or corticosterone stress, whereas inhibition of JNK facilitates regrowth of spines even in the continued presence of glucocorticoid. This identifies that JNK acts locally in the spine-head to promote AMPAR internalization and spine shrinkage following stress, and reveals a protective function for JNK inhibition in preventing spine regression.
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16
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Banerjee S, Mitra D. Structural Basis of Design and Engineering for Advanced Plant Optogenetics. TRENDS IN PLANT SCIENCE 2020; 25:35-65. [PMID: 31699521 DOI: 10.1016/j.tplants.2019.10.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 09/12/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
In optogenetics, light-sensitive proteins are specifically expressed in target cells and light is used to precisely control the activity of these proteins at high spatiotemporal resolution. Optogenetics initially used naturally occurring photoreceptors to control neural circuits, but has expanded to include carefully designed and engineered photoreceptors. Several optogenetic constructs are based on plant photoreceptors, but their application to plant systems has been limited. Here, we present perspectives on the development of plant optogenetics, considering different levels of design complexity. We discuss how general principles of light-driven signal transduction can be coupled with approaches for engineering protein folding to develop novel optogenetic tools. Finally, we explore how the use of computation, networks, circular permutation, and directed evolution could enrich optogenetics.
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Affiliation(s)
- Sudakshina Banerjee
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata 700073, India
| | - Devrani Mitra
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata 700073, India.
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17
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Abstract
The transport of proteins between the nucleus and the cytosol is a vital process regulating cellular activity. The ability to spatiotemporally control the nucleocytoplasmic transport of a protein of interest allows for elucidating its function taking into account the dynamic and heterogeneous nature of biological processes contrary to conventional knockin, knockout, and chemically induced overexpression strategies. We recently developed two optogenetic tools, called LINuS and LEXY, for reversibly controlling with blue light the nuclear import and export of proteins of interest, respectively. Here we describe how to use them to control the localization of a protein of interest in cultured mammalian cells using a fluorescence microscope.
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Affiliation(s)
- Daniel Weis
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Barbara Di Ventura
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany. .,Institute of Biology II, University of Freiburg, Freiburg, Germany.
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18
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Nakasone Y, Takaramoto S, Terazima M. Time-Resolved Diffusion Detection with Microstopped Flow System. Anal Chem 2019; 91:11987-11993. [PMID: 31442029 DOI: 10.1021/acs.analchem.9b02897] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transient grating (TG) method is a powerful technique for monitoring the time dependence of the diffusion coefficient during photochemical reactions. However, the applications of this technique have been limited to photochemical reactions. Here, a microstopped flow (μ-SF) system is developed to expand the technique's applicability. The constructed μ-SF system can be used for a solution with a total volume as small as 3 μL, and mixing times for absorption and diffusion measurements were determined to be 400 μs and 100 ms, respectively. To demonstrate this system with the TG method, an acid-induced denaturation of a photosensor protein, phototropin LOV2 domain with a linker, was studied from the viewpoint of the reactivity. This system can be used not only for time-resolved diffusion measurement but also for conventional absorption or fluorescence detection methods. In particular, this system has a great advantage for a target solution in that only a very small amount is needed.
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Affiliation(s)
- Yusuke Nakasone
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto 606-8502 , Japan
| | - Shunki Takaramoto
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto 606-8502 , Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto 606-8502 , Japan
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19
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Dagliyan O, Dokholyan NV, Hahn KM. Engineering proteins for allosteric control by light or ligands. Nat Protoc 2019; 14:1863-1883. [PMID: 31076662 PMCID: PMC6648709 DOI: 10.1038/s41596-019-0165-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Accepted: 03/12/2019] [Indexed: 01/02/2023]
Abstract
Control of protein activity in living cells can reveal the role of spatiotemporal dynamics in signaling circuits. Protein analogs with engineered allosteric responses can be particularly effective in the interrogation of protein signaling, as they can replace endogenous proteins with minimal perturbation of native interactions. However, it has been a challenge to identify allosteric sites in target proteins where insertion of responsive domains produces an allosteric response comparable to the activity of native proteins. Here, we describe a detailed protocol to generate genetically encoded analogs of proteins that can be allosterically controlled by either rapamycin or blue light, as well as experimental procedures to produce and test these analogs in vitro and in mammalian cell lines. We describe computational methods, based on crystal structures or homology models, to identify effective sites for insertion of either an engineered rapamycin-responsive (uniRapR) domain or the light-responsive light-oxygen-voltage 2 (LOV2) domain. The inserted domains allosterically regulate the active site, responding to rapamycin with irreversible activation, or to light with reversible inactivation at higher spatial and temporal resolution. These strategies have been successfully applied to catalytic domains of protein kinases, Rho family GTPases, and guanine exchange factors (GEFs), as well as the binding domain of a GEF Vav2. Computational tasks can be completed within a few hours, followed by 1-2 weeks of experimental validation. We provide protocols for computational design, cloning, and experimental testing of the engineered proteins, using Src tyrosine kinase, GEF Vav2, and Rho GTPase Rac1 as examples.
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Affiliation(s)
- Onur Dagliyan
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Nikolay V Dokholyan
- Departments of Pharmacology and of Biochemistry & Molecular Biology, Penn State College of Medicine, Hershey, PA, USA
| | - Klaus M Hahn
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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20
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Kalvaitis ME, Johnson LA, Mart RJ, Rizkallah P, Allemann RK. A Noncanonical Chromophore Reveals Structural Rearrangements of the Light-Oxygen-Voltage Domain upon Photoactivation. Biochemistry 2019; 58:2608-2616. [PMID: 31082213 PMCID: PMC7007005 DOI: 10.1021/acs.biochem.9b00255] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
![]()
Light-oxygen-voltage
(LOV) domains are increasingly used to engineer
photoresponsive biological systems. While the photochemical cycle
is well documented, the allosteric mechanism by which formation of
a cysteinyl-flavin adduct leads to activation is unclear. Via replacement
of flavin mononucleotide (FMN) with 5-deazaflavin mononucleotide (5dFMN)
in the Aureochrome1a (Au1a) transcription factor from Ochromonas
danica, a thermally stable cysteinyl-5dFMN adduct was generated.
High-resolution crystal structures (<2 Å) under different
illumination conditions with either FMN or 5dFMN chromophores reveal
three conformations of the highly conserved glutamine 293. An allosteric
hydrogen bond network linking the chromophore via Gln293 to the auxiliary
A′α helix is observed. With FMN, a “flip”
of the Gln293 side chain occurs between dark and lit states. 5dFMN
cannot hydrogen bond through the C5 position and proved to be unable
to support Au1a domain dimerization. Under blue light, the Gln293
side chain instead “swings” away in a conformation distal
to the chromophore and not previously observed in existing LOV domain
structures. Together, the multiple side chain conformations of Gln293
and functional analysis of 5dFMN provide new insight into the structural
requirements for LOV domain activation.
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Affiliation(s)
- Mindaugas E Kalvaitis
- School of Chemistry , Cardiff University , Park Place , Cardiff CF10 3AT , United Kingdom
| | - Luke A Johnson
- School of Chemistry , Cardiff University , Park Place , Cardiff CF10 3AT , United Kingdom
| | - Robert J Mart
- School of Chemistry , Cardiff University , Park Place , Cardiff CF10 3AT , United Kingdom
| | - Pierre Rizkallah
- School of Medicine , University Hospital Wales , Main Building, Heath Park , Cardiff CF14 4XN , United Kingdom
| | - Rudolf K Allemann
- School of Chemistry , Cardiff University , Park Place , Cardiff CF10 3AT , United Kingdom
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21
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Zayner JP, Mathes T, Sosnick TR, Kennis JTM. Helical Contributions Mediate Light-Activated Conformational Change in the LOV2 Domain of Avena sativa Phototropin 1. ACS OMEGA 2019; 4:1238-1243. [PMID: 31459397 PMCID: PMC6648828 DOI: 10.1021/acsomega.8b02872] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/02/2019] [Indexed: 06/10/2023]
Abstract
Algae, plants, bacteria, and fungi contain flavin-binding light-oxygen-voltage (LOV) domains that function as blue light sensors to control cellular responses to light. In the second LOV domain of phototropins, called LOV2 domains, blue light illumination leads to covalent bond formation between protein and flavin that induces the dissociation and unfolding of a C-terminally attached α helix (Jα) and the N-terminal helix (A'α). To date, the majority of studies on these domains have focused on versions that contain truncations in the termini, which creates difficulties when extrapolating to the much larger proteins that contain these domains. Here, we study the influence of deletions and extensions of the A'α helix of the LOV2 domain of Avena sativa phototropin 1 (AsLOV2) on the light-triggered structural response of the protein by Fourier-transform infrared difference spectroscopy. Deletion of the A'α helix abolishes the light-induced unfolding of Jα, whereas extensions of the A'α helix lead to an attenuated structural change of Jα. These results are different from shorter constructs, indicating that the conformational changes in full-length phototropin LOV domains might not be as large as previously assumed, and that the well-characterized full unfolding of the Jα helix in AsLOV2 with short A'α helices may be considered a truncation artifact. It also suggests that the N- and C-terminal helices of phot-LOV2 domains are necessary for allosteric regulation of the phototropin kinase domain and may provide a basis for signal integration of LOV1 and LOV2 domains in phototropins.
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Affiliation(s)
- Josiah P. Zayner
- Department of Biochemistry
and Molecular Biology, The University of
Chicago, Chicago 60637, United States
| | - Tilo Mathes
- Biophysics
Section, Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Tobin R. Sosnick
- Department of Biochemistry
and Molecular Biology, The University of
Chicago, Chicago 60637, United States
- Institute
for Biophysical Dynamics, The University
of Chicago, Chicago, Illinois 60637 United States
| | - John T. M. Kennis
- Biophysics
Section, Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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22
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Applications of molecular modeling to flavoproteins: Insights and challenges. Methods Enzymol 2019; 620:277-314. [DOI: 10.1016/bs.mie.2019.03.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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23
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Affiliation(s)
- Mareike Daniela Hoffmann
- Department of Theoretical Bioinformatics; German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Synthetic Biology Group; Institute for Pharmacy and Biotechnology (IPMB) and Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant); University of Heidelberg; Im Neuenheimer Feld 267 69120 Heidelberg Germany
| | - Felix Bubeck
- Synthetic Biology Group; Institute for Pharmacy and Biotechnology (IPMB) and Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant); University of Heidelberg; Im Neuenheimer Feld 267 69120 Heidelberg Germany
| | - Roland Eils
- Department of Theoretical Bioinformatics; German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Synthetic Biology Group; Institute for Pharmacy and Biotechnology (IPMB) and Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant); University of Heidelberg; Im Neuenheimer Feld 267 69120 Heidelberg Germany
- Digital Health Center; Berlin Institute of Health (BIH) and Charité-University Medicine Berlin; 10117 Berlin Germany
- Health Data Science Unit; University Hospital Heidelberg; 10117 Heidelberg Germany
| | - Dominik Niopek
- Department of Theoretical Bioinformatics; German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Synthetic Biology Group; Institute for Pharmacy and Biotechnology (IPMB) and Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant); University of Heidelberg; Im Neuenheimer Feld 267 69120 Heidelberg Germany
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24
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Abstract
The first stage in biological signaling is based on changes in the functional state of a receptor protein triggered by interaction of the receptor with its ligand(s). The light-triggered nature of photoreceptors allows studies on the mechanism of such changes in receptor proteins using a wide range of biophysical methods and with superb time resolution. Here, we critically evaluate current understanding of proton and electron transfer in photosensory proteins and their involvement both in primary photochemistry and subsequent processes that lead to the formation of the signaling state. An insight emerging from multiple families of photoreceptors is that ultrafast primary photochemistry is followed by slower proton transfer steps that contribute to triggering large protein conformational changes during signaling state formation. We discuss themes and principles for light sensing shared by the six photoreceptor families: rhodopsins, phytochromes, photoactive yellow proteins, light-oxygen-voltage proteins, blue-light sensors using flavin, and cryptochromes.
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Affiliation(s)
- Tilman Kottke
- Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Aihua Xie
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
| | - Delmar S. Larsen
- Department of Chemistry, University of California, Davis, California 95616, USA
| | - Wouter D. Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, USA
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25
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Magerl K, Stambolic I, Dick B. Switching from adduct formation to electron transfer in a light-oxygen-voltage domain containing the reactive cysteine. Phys Chem Chem Phys 2018; 19:10808-10819. [PMID: 28271102 DOI: 10.1039/c6cp08370f] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
LOV (light-, oxygen- or voltage-sensitive) domains act as photosensory units of many prokaryotic and eukaryotic proteins. Upon blue light excitation they undergo a photocycle via the excited triplet state of their flavin chromophore yielding the flavin-cysteinyl adduct. Adduct formation is highly conserved among all LOV domains and constitutes the primary step of LOV domain signaling. But recently, it has been shown that signal propagation can also be triggered by flavin photoreduction to the neutral semiquinone offering new prospects for protein engineering. This, however, requires mutation of the photo-active Cys. Here, we report on LOV1 mutants of C. reinhardtii phototropin in which adduct formation is suppressed although the photo-active Cys is present. Introduction of a Tyr into the LOV core induces a proton coupled electron transfer towards the flavin chromophore. Flavin radical species are formed via either the excited flavin singlet or triplet state depending on the geometry of donor and acceptor. This photoreductive pathway resembles the photoreaction observed in other blue light photoreceptors, e.g. blue-light sensors using flavin adenine dinucleotide (BLUF) domains or cryptochromes. The ability to tune the photoreactivity of the flavin chromophore inside the LOV core has implications for the mechanism of adduct formation in the wild type and may be of use for protein engineering.
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Affiliation(s)
- Kathrin Magerl
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany.
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26
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Boesmans W, Hao MM, Vanden Berghe P. Optogenetic and chemogenetic techniques for neurogastroenterology. Nat Rev Gastroenterol Hepatol 2018; 15:21-38. [PMID: 29184183 DOI: 10.1038/nrgastro.2017.151] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Optogenetics and chemogenetics comprise a wide variety of applications in which genetically encoded actuators and indicators are used to modulate and monitor activity with high cellular specificity. Over the past 10 years, development of these genetically encoded tools has contributed tremendously to our understanding of integrated physiology. In concert with the continued refinement of probes, strategies to target transgene expression to specific cell types have also made much progress in the past 20 years. In addition, the successful implementation of optogenetic and chemogenetic techniques thrives thanks to ongoing advances in live imaging microscopy and optical technology. Although innovation of optogenetic and chemogenetic methods has been primarily driven by researchers studying the central nervous system, these techniques also hold great promise to boost research in neurogastroenterology. In this Review, we describe the different classes of tools that are currently available and give an overview of the strategies to target them to specific cell types in the gut wall. We discuss the possibilities and limitations of optogenetic and chemogenetic technology in the gut and provide an overview of their current use, with a focus on the enteric nervous system. Furthermore, we suggest some experiments that can advance our understanding of how the intrinsic and extrinsic neural networks of the gut control gastrointestinal function.
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Affiliation(s)
- Werend Boesmans
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Herestraat 49, O&N 1 Box 701, 3000 Leuven, Belgium.,Department of Pathology, Maastricht University Medical Center, P. Debeijelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Marlene M Hao
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Herestraat 49, O&N 1 Box 701, 3000 Leuven, Belgium.,Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Pieter Vanden Berghe
- Laboratory for Enteric Neuroscience (LENS), Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Herestraat 49, O&N 1 Box 701, 3000 Leuven, Belgium
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27
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Gehrig S, Macpherson JA, Driscoll PC, Symon A, Martin SR, MacRae JI, Kleinjung J, Fraternali F, Anastasiou D. An engineered photoswitchable mammalian pyruvate kinase. FEBS J 2017; 284:2955-2980. [PMID: 28715126 PMCID: PMC5637921 DOI: 10.1111/febs.14175] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 06/24/2017] [Accepted: 07/13/2017] [Indexed: 01/06/2023]
Abstract
Changes in allosteric regulation of glycolytic enzymes have been linked to metabolic reprogramming involved in cancer. Remarkably, allosteric mechanisms control enzyme function at significantly shorter time-scales compared to the long-term effects of metabolic reprogramming on cell proliferation. It remains unclear if and how the speed and reversibility afforded by rapid allosteric control of metabolic enzymes is important for cell proliferation. Tools that allow specific, dynamic modulation of enzymatic activities in mammalian cells would help address this question. Towards this goal, we have used molecular dynamics simulations to guide the design of mPKM2 internal light/oxygen/voltage-sensitive domain 2 (LOV2) fusion at position D24 (PiL[D24]), an engineered pyruvate kinase M2 (PKM2) variant that harbours an insertion of the light-sensing LOV2 domain from Avena Sativa within a region implicated in allosteric regulation by fructose 1,6-bisphosphate (FBP). The LOV2 photoreaction is preserved in the PiL[D24] chimera and causes secondary structure changes that are associated with a 30% decrease in the Km of the enzyme for phosphoenolpyruvate resulting in increased pyruvate kinase activity after light exposure. Importantly, this change in activity is reversible upon light withdrawal. Expression of PiL[D24] in cells leads to light-induced increase in labelling of pyruvate from glucose. PiL[D24] therefore could provide a means to modulate cellular glucose metabolism in a remote manner and paves the way for studying the importance of rapid allosteric phenomena in the regulation of metabolism and enzyme control.
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Affiliation(s)
- Stefanie Gehrig
- Cancer Metabolism LaboratoryThe Francis Crick InstituteLondonUK
| | | | - Paul C. Driscoll
- Metabolomics Science Technology PlatformThe Francis Crick InstituteLondonUK
| | - Alastair Symon
- Instrument Prototyping Science Technology PlatformThe Francis Crick InstituteLondonUK
| | - Stephen R. Martin
- Structural Biology Science Technology PlatformThe Francis Crick InstituteLondonUK
| | - James I. MacRae
- Metabolomics Science Technology PlatformThe Francis Crick InstituteLondonUK
| | - Jens Kleinjung
- Computational BiologyThe Francis Crick InstituteLondonUK
| | - Franca Fraternali
- Randall Division of Cell and Molecular BiophysicsKing's CollegeLondonUK
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28
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Zhou H, Zoltowski BD, Tao P. Revealing Hidden Conformational Space of LOV Protein VIVID Through Rigid Residue Scan Simulations. Sci Rep 2017; 7:46626. [PMID: 28425502 PMCID: PMC5397860 DOI: 10.1038/srep46626] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/21/2017] [Indexed: 01/11/2023] Open
Abstract
VIVID(VVD) protein is a Light-Oxygen-Voltage(LOV) domain in circadian clock system. Upon blue light activation, a covalent bond is formed between VVD residue Cys108 and its cofactor flavin adenine dinucleotide(FAD), and prompts VVD switching from Dark state to Light state with significant conformational deviation. However, the mechanism of this local environment initiated global protein conformational change remains elusive. We employed a recently developed computational approach, rigid residue scan(RRS), to systematically probe the impact of the internal degrees of freedom in each amino acid residue of VVD on its overall dynamics by applying rigid body constraint on each residue in molecular dynamics simulations. Key residues were identified with distinctive impacts on Dark and Light states, respectively. All the simulations display wide range of distribution on a two-dimensional(2D) plot upon structural root-mean-square deviations(RMSD) from either Dark or Light state. Clustering analysis of the 2D RMSD distribution leads to 15 representative structures with drastically different conformation of N-terminus, which is also a key difference between Dark and Light states of VVD. Further principle component analyses(PCA) of RRS simulations agree with the observation of distinctive impact from individual residues on Dark and Light states.
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Affiliation(s)
- Hongyu Zhou
- Department of Chemistry, Center for Drug Discovery, Design, and Delivery(CD4), Center for Scientific Computation, Southern Methodist University, Dallas, Texas 75275, United States of America
| | - Brian D Zoltowski
- Department of Chemistry, Center for Drug Discovery, Design, and Delivery(CD4), Center for Scientific Computation, Southern Methodist University, Dallas, Texas 75275, United States of America
| | - Peng Tao
- Department of Chemistry, Center for Drug Discovery, Design, and Delivery(CD4), Center for Scientific Computation, Southern Methodist University, Dallas, Texas 75275, United States of America
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29
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Gil AA, Laptenok SP, French JB, Iuliano JN, Lukacs A, Hall CR, Sazanovich IV, Greetham GM, Bacher A, Illarionov B, Fischer M, Tonge PJ, Meech SR. Femtosecond to Millisecond Dynamics of Light Induced Allostery in the Avena sativa LOV Domain. J Phys Chem B 2017; 121:1010-1019. [PMID: 28068090 DOI: 10.1021/acs.jpcb.7b00088] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The rational engineering of photosensor proteins underpins the field of optogenetics, in which light is used for spatiotemporal control of cell signaling. Optogenetic elements function by converting electronic excitation of an embedded chromophore into structural changes on the microseconds to seconds time scale, which then modulate the activity of output domains responsible for biological signaling. Using time-resolved vibrational spectroscopy coupled with isotope labeling, we have mapped the structural evolution of the LOV2 domain of the flavin binding phototropin Avena sativa (AsLOV2) over 10 decades of time, reporting structural dynamics between 100 fs and 1 ms after optical excitation. The transient vibrational spectra contain contributions from both the flavin chromophore and the surrounding protein matrix. These contributions are resolved and assigned through the study of four different isotopically labeled samples. High signal-to-noise data permit the detailed analysis of kinetics associated with the light activated structural evolution. A pathway for the photocycle consistent with the data is proposed. The earliest events occur in the flavin binding pocket, where a subpicosecond perturbation of the protein matrix occurs. In this perturbed environment, the previously characterized reaction between triplet state isoalloxazine and an adjacent cysteine leads to formation of the adduct state; this step is shown to exhibit dispersive kinetics. This reaction promotes coupling of the optical excitation to successive time-dependent structural changes, initially in the β-sheet and then α-helix regions of the AsLOV2 domain, which ultimately gives rise to Jα-helix unfolding, yielding the signaling state. This model is tested through point mutagenesis, elucidating in particular the key mediating role played by Q513.
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Affiliation(s)
- Agnieszka A Gil
- Department of Chemistry, Stony Brook University , New York 11794-3400, United States
| | - Sergey P Laptenok
- School of Chemistry, University of East Anglia , Norwich, NR4 7TJ, U.K
| | - Jarrod B French
- Department of Chemistry, Stony Brook University , New York 11794-3400, United States
| | - James N Iuliano
- Department of Chemistry, Stony Brook University , New York 11794-3400, United States
| | - Andras Lukacs
- School of Chemistry, University of East Anglia , Norwich, NR4 7TJ, U.K.,Department of Biophysics, Medical School, University of Pecs , Szigeti ut 12, 7624 Pecs, Hungary
| | | | - Igor V Sazanovich
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory , Didcot, Oxon OX11 0QX, U.K
| | - Gregory M Greetham
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory , Didcot, Oxon OX11 0QX, U.K
| | - Adelbert Bacher
- Department Chemie, Technische Universität München , D-85747 Garching, Germany
| | - Boris Illarionov
- Institut für Biochemie und Lebensmittelchemie, Universität Hamburg , Grindelallee 117, D-20146 Hamburg, Germany
| | - Markus Fischer
- Institut für Biochemie und Lebensmittelchemie, Universität Hamburg , Grindelallee 117, D-20146 Hamburg, Germany
| | - Peter J Tonge
- Department of Chemistry, Stony Brook University , New York 11794-3400, United States
| | - Stephen R Meech
- School of Chemistry, University of East Anglia , Norwich, NR4 7TJ, U.K
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30
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Konold PE, Mathes T, Weiβenborn J, Groot ML, Hegemann P, Kennis JTM. Unfolding of the C-Terminal Jα Helix in the LOV2 Photoreceptor Domain Observed by Time-Resolved Vibrational Spectroscopy. J Phys Chem Lett 2016; 7:3472-6. [PMID: 27537211 DOI: 10.1021/acs.jpclett.6b01484] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Light-triggered reactions of biological photoreceptors have gained immense attention for their role as molecular switches in their native organisms and for optogenetic application. The light, oxygen, and voltage 2 (LOV2) sensing domain of plant phototropin binds a C-terminal Jα helix that is docked on a β-sheet and unfolds upon light absorption by the flavin mononucleotide (FMN) chromophore. In this work, the signal transduction pathway of LOV2 from Avena sativa was investigated using time-resolved infrared spectroscopy from picoseconds to microseconds. In D2O buffer, FMN singlet-to-triplet conversion occurs in 2 ns and formation of the covalent cysteinyl-FMN adduct in 10 μs. We observe a two-step unfolding of the Jα helix: The first phase occurs concomitantly with Cys-FMN covalent adduct formation in 10 μs, along with hydrogen-bond rupture of the FMN C4═O with Gln-513, motion of the β-sheet, and an additional helical element. The second phase occurs in approximately 240 μs. The final spectrum at 500 μs is essentially identical to the steady-state light-minus-dark Fourier transform infrared spectrum, indicating that Jα helix unfolding is complete on that time scale.
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Affiliation(s)
- Patrick E Konold
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit , 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Tilo Mathes
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit , 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Jörn Weiβenborn
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit , 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Marie Louise Groot
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit , 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Peter Hegemann
- Department of Biology, Experimental Biophysics, Humboldt-Universität zu Berlin , Invalidenstraße 42, 10115 Berlin, Germany
| | - John T M Kennis
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit , 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
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31
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Wehler P, Niopek D, Eils R, Di Ventura B. Optogenetic Control of Nuclear Protein Import in Living Cells Using Light-Inducible Nuclear Localization Signals (LINuS). ACTA ACUST UNITED AC 2016; 8:131-145. [PMID: 27258691 DOI: 10.1002/cpch.4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Many biological processes are regulated by the timely import of specific proteins into the nucleus. The ability to spatiotemporally control the nuclear import of proteins of interest therefore allows study of their role in a given biological process as well as controlling this process in space and time. The light-inducible nuclear localization signal (LINuS) was developed based on a natural plant photoreceptor that reversibly triggers the import of proteins of interest into the nucleus with blue light. Each LINuS is a small, genetically encoded domain that is fused to the protein of interest at the N or C terminus. These protocols describe how to carry out initial microscopy-based screening to assess which LINuS variant works best with a protein of interest. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- Pierre Wehler
- Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant), University of Heidelberg, Heidelberg, Germany
| | - Dominik Niopek
- Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant), University of Heidelberg, Heidelberg, Germany
- Department of Bioinformatics and Functional Genomics, Institute for Pharmacy and Biotechnology
- Department of Theoretical Bioinformatics, German Cancer Research Center, Heidelberg, Germany
| | - Roland Eils
- Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant), University of Heidelberg, Heidelberg, Germany
- Department of Bioinformatics and Functional Genomics, Institute for Pharmacy and Biotechnology
- Department of Theoretical Bioinformatics, German Cancer Research Center, Heidelberg, Germany
| | - Barbara Di Ventura
- Center for Quantitative Analysis of Molecular and Cellular Biosystems (BioQuant), University of Heidelberg, Heidelberg, Germany
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32
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Peter EK, Shea JE, Pivkin IV. Coarse kMC-based replica exchange algorithms for the accelerated simulation of protein folding in explicit solvent. Phys Chem Chem Phys 2016; 18:13052-65. [DOI: 10.1039/c5cp06867c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In this paper, we present a coarse replica exchange molecular dynamics (REMD) approach, based on kinetic Monte Carlo (kMC).
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Affiliation(s)
- Emanuel K. Peter
- Institute of Computational Science
- Faculty of Informatics
- University of Lugano
- Switzerland
| | - Joan-Emma Shea
- Department of Chemistry and Biochemistry
- Department of Physics
- University of California
- Santa Barbara
- USA
| | - Igor V. Pivkin
- Institute of Computational Science
- Faculty of Informatics
- University of Lugano
- Switzerland
- Swiss Institute of Bioinformatics
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33
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Lee R, Gam J, Moon J, Lee SG, Suh YG, Lee BJ, Lee J. A critical element of the light-induced quaternary structural changes in YtvA-LOV. Protein Sci 2015; 24:1997-2007. [PMID: 26402155 DOI: 10.1002/pro.2810] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 09/18/2015] [Accepted: 09/19/2015] [Indexed: 01/27/2023]
Abstract
YtvA, a photosensory LOV (light-oxygen-voltage) protein from Bacillus subtilis, exists as a dimer that previously appeared to undergo surprisingly small structural changes after light illumination compared with other light-sensing proteins. However, we now report that light induces significant structural perturbations in a series of YtvA-LOV domain derivatives in which the Jα helix has been truncated or replaced. Results from native gel analysis showed significant mobility changes in these derivatives after light illumination; YtvA-LOV without the Jα helix dimerized in the dark state but existed as a monomer in the light state. The absence of the Jα helix also affected the dark regeneration kinetics and the stability of the flavin mononucleotide (FMN) binding to its binding site. Our results demonstrate an alternative way of photo-induced signal propagation that leads to a bigger functional response through dimer/monomer conversions of the YtvA-LOV than the local disruption of Jα helix in the As-LOV domain.
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Affiliation(s)
- Rang Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Korea
| | - Jongsik Gam
- Department of Medicinal Bioscience, College of Interdisciplinary & Creative Studies, Konyang University, Nonsan-Si, 320-711, Korea
| | - Jayoung Moon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Korea
| | - Seung-Goo Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea
| | - Young-Ger Suh
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Korea
| | - Bong-Jin Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Korea
| | - Jeeyeon Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Korea
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34
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Bocola M, Schwaneberg U, Jaeger KE, Krauss U. Light-induced structural changes in a short light, oxygen, voltage (LOV) protein revealed by molecular dynamics simulations-implications for the understanding of LOV photoactivation. Front Mol Biosci 2015; 2:55. [PMID: 26484348 PMCID: PMC4589677 DOI: 10.3389/fmolb.2015.00055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 09/05/2015] [Indexed: 02/06/2023] Open
Abstract
The modularity of light, oxygen, voltage (LOV) blue-light photoreceptors has recently been exploited for the design of LOV-based optogenetic tools, which allow the light-dependent control of biological functions. For the understanding of LOV sensory function and hence the optimal design of LOV-based optogentic tools it is essential to gain an in depth atomic-level understanding of the underlying photoactivation and intramolecular signal-relay mechanisms. To address this question we performed molecular dynamics simulations on both the dark- and light-adapted state of PpSB1-LOV, a short dimeric bacterial LOV-photoreceptor protein, recently crystallized under constant illumination. While LOV dimers remained globally stable during the light-state simulation with regard to the Jα coiled-coil, distinct conformational changes for a glutamine in the vicinity of the FMN chromophore are observed. In contrast, multiple Jα-helix conformations are sampled in the dark-state. These changes coincide with a displacement of the Iβ and Hβ strands relative to the light-state structure and result in a correlated rotation of both LOV core domains in the dimer. These global changes are most likely initiated by the reorientation of the conserved glutamine Q116, whose side chain flips between the Aβ (dark state) and Hβ strand (light state), while maintaining two potential hydrogen bonds to FMN-N5 and FMN-O4, respectively. This local Q116-FMN reorientation impacts on an inter-subunit salt-bridge (K117-E96), which is stabilized in the light state, hence accounting for the observed decreased mobility. Based on these findings we propose an alternative mechanism for dimeric LOV photoactivation and intramolecular signal-relay, assigning a distinct structural role for the conserved “flipping” glutamine. The proposed mechanism is discussed in light of universal applicability and its implications for the understanding of LOV-based optogenetic tools.
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Affiliation(s)
- Marco Bocola
- Lehrstuhl für Biotechnologie, RWTH Aachen University Aachen, Germany
| | | | - Karl-Erich Jaeger
- Forschungszentrum Jülich, Institut für Molekulare Enzymtechnologie, Heinrich Heine University Düsseldorf Jülich, Germany ; Forschungszentrum Jülich, Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie Jülich, Germany
| | - Ulrich Krauss
- Forschungszentrum Jülich, Institut für Molekulare Enzymtechnologie, Heinrich Heine University Düsseldorf Jülich, Germany
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35
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Winkler A, Barends TRM, Udvarhelyi A, Lenherr-Frey D, Lomb L, Menzel A, Schlichting I. Structural details of light activation of the LOV2-based photoswitch PA-Rac1. ACS Chem Biol 2015; 10:502-9. [PMID: 25368973 DOI: 10.1021/cb500744m] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Optical control of cellular processes is an emerging approach for studying biological systems, affording control with high spatial and temporal resolution. Specifically designed artificial photoswitches add an interesting extension to naturally occurring light-regulated functionalities. However, despite a great deal of structural information, the generation of new tools cannot be based fully on rational design yet; in many cases design is limited by our understanding of molecular details of light activation and signal transduction. Our biochemical and biophysical studies on the established optogenetic tool PA-Rac1, the photoactivatable small GTPase Rac1, reveal how unexpected details of the sensor-effector interface, such as metal coordination, significantly affect functionally important structural elements of this photoswitch. Together with solution scattering experiments, our results favor differences in the population of pre-existing conformations as the underlying allosteric activation mechanism of PA-Rac1, rather than the assumed release of the Rac1 domain from the caging photoreceptor domain. These results have implications for the design of new optogenetic tools and highlight the importance of including molecular details of the sensor-effector interface, which is however difficult to assess during the initial design of novel artificial photoswitches.
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Affiliation(s)
- Andreas Winkler
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Thomas R. M. Barends
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Anikó Udvarhelyi
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Daniel Lenherr-Frey
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Lukas Lomb
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Andreas Menzel
- Paul Scherrer Institute, PSI, 5232 Villigen, Switzerland
| | - Ilme Schlichting
- Department
of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
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36
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Peter E, Dick B, Stambolic I, Baeurle SA. Exploring the multiscale signaling behavior of phototropin1 from Chlamydomonas reinhardtii using a full-residue space kinetic Monte Carlo molecular dynamics technique. Proteins 2014; 82:2018-40. [PMID: 24623633 DOI: 10.1002/prot.24556] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 02/19/2014] [Accepted: 03/10/2014] [Indexed: 12/21/2022]
Abstract
Devising analysis tools for elucidating the regulatory mechanism of complex enzymes has been a challenging task for many decades. It generally requires the determination of the structural-dynamical information of protein solvent systems far from equilibrium over multiple length and time scales, which is still difficult both theoretically and experimentally. To cope with the problem, we introduce a full-residue space multiscale simulation method based on a combination of the kinetic Monte Carlo and molecular dynamics techniques, in which the rates of the rate-determining processes are evaluated from a biomolecular forcefield on the fly during the simulation run by taking into account the full space of residues. To demonstrate its reliability and efficiency, we explore the light-induced functional behavior of the full-length phototropin1 from Chlamydomonas reinhardtii (Cr-phot1) and its various subdomains. Our results demonstrate that in the dark state the light oxygen voltage-2-Jα (LOV2-Jα) photoswitch inhibits the enzymatic activity of the kinase, whereas the LOV1-Jα photoswitch controls the dimerization with the LOV2 domain. This leads to the repulsion of the LOV1-LOV2 linker out of the interface region between both LOV domains, which results in a positively charged surface suitable for cell-membrane interaction. By contrast, in the light state, we observe that the distance between both LOV domains is increased and the LOV1-LOV2 linker forms a helix-turn-helix (HTH) motif, which enables gene control through nucleotide binding. Finally, we find that the kinase is activated through the disruption of the Jα-helix from the LOV2 domain, which is followed by a stretching of the activation loop (A-loop) and broadening of the catalytic cleft of the kinase.
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Affiliation(s)
- Emanuel Peter
- Department of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93040, Regensburg, Germany
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37
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Zayner JP, Antoniou C, French AR, Hause RJ, Sosnick TR. Investigating models of protein function and allostery with a widespread mutational analysis of a light-activated protein. Biophys J 2014; 105:1027-36. [PMID: 23972854 DOI: 10.1016/j.bpj.2013.07.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/17/2013] [Accepted: 07/01/2013] [Indexed: 10/26/2022] Open
Abstract
To investigate the relationship between a protein's sequence and its biophysical properties, we studied the effects of more than 100 mutations in Avena sativa light-oxygen-voltage domain 2, a model protein of the Per-Arnt-Sim family. The A. sativa light-oxygen-voltage domain 2 undergoes a photocycle with a conformational change involving the unfolding of the terminal helices. Whereas selection studies typically search for winners in a large population and fail to characterize many sites, we characterized the biophysical consequences of mutations throughout the protein using NMR, circular dichroism, and ultraviolet/visible spectroscopy. Despite our intention to introduce highly disruptive substitutions, most had modest or no effect on function, and many could even be considered to be more photoactive. Substitutions at evolutionarily conserved sites can have minimal effect, whereas those at nonconserved positions can have large effects, contrary to the view that the effects of mutations, especially at conserved positions, are predictable. Using predictive models, we found that the effects of mutations on biophysical function and allostery reflect a complex mixture of multiple characteristics including location, character, electrostatics, and chemistry.
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Affiliation(s)
- Josiah P Zayner
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
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38
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Freddolino PL, Gardner KH, Schulten K. Signaling mechanisms of LOV domains: new insights from molecular dynamics studies. Photochem Photobiol Sci 2014; 12:1158-70. [PMID: 23407663 DOI: 10.1039/c3pp25400c] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Phototropins are one of several classes of photoreceptors used by plants and algae to respond to light. These proteins contain flavin-binding LOV (Light-Oxygen-Voltage) domains that form covalent cysteine-flavin adducts upon exposure to blue light, leading to the enhancement of phototropin kinase activity. Several lines of evidence suggest that adduct formation in the phototropin LOV2 domains leads to the dissociation of an alpha helix (Jα) from these domains as part of the light-induced activation process. However, crystal structures of LOV domains both in the presence and absence of the Jα helix show very few differences between dark and illuminated states, and thus the precise mechanism through which adduct formation triggers helical dissociation remains poorly understood. Using Avena sativa phototropin 1 LOV2 as a model system, we have studied the interactions of the LOV domain core with the Jα helix through a series of equilibrium molecular dynamics simulations. Here we show that conformational transitions of a conserved glutamine residue in the flavin binding pocket are coupled to altered dynamics of the Jα helix both through a shift in dynamics of the main β-sheet of the LOV domain core and through a secondary pathway involving the N-terminal A'α helix.
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Affiliation(s)
- Peter L Freddolino
- Joint Centers for Systems Biology, Columbia University, New York, NY, USA
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39
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Domratcheva T, Udvarhelyi A, Shahi ARM. Computational spectroscopy, dynamics, and photochemistry of photosensory flavoproteins. Methods Mol Biol 2014; 1146:191-228. [PMID: 24764094 DOI: 10.1007/978-1-4939-0452-5_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Extensive interest in photosensory proteins stimulated computational studies of flavins and flavoproteins in the past decade. This review is dedicated to the three central topics of these studies: calculations of flavin UV-visible and IR spectra, simulated dynamics of photoreceptor proteins, and flavin photochemistry. Accordingly, this chapter is divided into three parts; each part describes corresponding computational protocols, summarizes computational results, and discusses the emerging mechanistic picture.
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Affiliation(s)
- Tatiana Domratcheva
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Jahnstraße 29, 69120, Heidelberg, Germany,
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40
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Conrad KS, Bilwes AM, Crane BR. Light-induced subunit dissociation by a light-oxygen-voltage domain photoreceptor from Rhodobacter sphaeroides. Biochemistry 2013; 52:378-91. [PMID: 23252338 DOI: 10.1021/bi3015373] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Light-oxygen-voltage (LOV) domains bind a flavin chromophore to serve as blue light sensors in a wide range of eukaryotic and prokaryotic proteins. LOV domains are associated with a variable effector domain or a separate protein signaling partner to execute a wide variety of functions that include regulation of kinases, generation of anti-sigma factor antagonists, and regulation of circadian clocks. Here we present the crystal structure, photocycle kinetics, association properties, and spectroscopic features of a full-length LOV domain protein from Rhodobacter sphaeroides (RsLOV). RsLOV exhibits N- and C-terminal helical extensions that form an unusual helical bundle at its dimer interface with some resemblance to the helical transducer of sensory rhodopsin II. The blue light-induced conformational changes of RsLOV revealed from a comparison of light- and dark-state crystal structures support a shared signaling mechanism of LOV domain proteins that originates with the light-induced formation of a flavin-cysteinyl photoadduct. Adduct formation disrupts hydrogen bonding in the active site and propagates structural changes through the LOV domain core to the N- and C-terminal extensions. Single-residue variants in the active site and dimer interface of RsLOV alter photoadduct lifetimes and induce structural changes that perturb the oligomeric state. Size exclusion chromatography, multiangle light scattering, small-angle X-ray scattering, and cross-linking studies indicate that RsLOV dimerizes in the dark but, upon light excitation, dissociates into monomers. This light-induced switch in oligomeric state may prove to be useful for engineering molecular associations in controlled cellular settings.
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Affiliation(s)
- Karen S Conrad
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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Peter E, Dick B, Baeurle SA. Regulatory mechanism of the light-activable allosteric switch LOV-TAP for the control of DNA binding: a computer simulation study. Proteins 2012; 81:394-405. [PMID: 23042418 DOI: 10.1002/prot.24196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 09/17/2012] [Accepted: 10/02/2012] [Indexed: 12/23/2022]
Abstract
The spatio-temporal control of gene expression is fundamental to elucidate cell proliferation and deregulation phenomena in living systems. Novel approaches based on light-sensitive multiprotein complexes have recently been devised, showing promising perspectives for the noninvasive and reversible modulation of the DNA-transcriptional activity in vivo. This has lately been demonstrated in a striking way through the generation of the artificial protein construct light-oxygen-voltage (LOV)-tryptophan-activated protein (TAP), in which the LOV-2-Jα photoswitch of phototropin1 from Avena sativa (AsLOV2-Jα) has been ligated to the tryptophan-repressor (TrpR) protein from Escherichia coli. Although tremendous progress has been achieved on the generation of such protein constructs, a detailed understanding of their functioning as opto-genetical tools is still in its infancy. Here, we elucidate the early stages of the light-induced regulatory mechanism of LOV-TAP at the molecular level, using the noninvasive molecular dynamics simulation technique. More specifically, we find that Cys450-FMN-adduct formation in the AsLOV2-Jα-binding pocket after photoexcitation induces the cleavage of the peripheral Jα-helix from the LOV core, causing a change of its polarity and electrostatic attraction of the photoswitch onto the DNA surface. This goes along with the flexibilization through unfolding of a hairpin-like helix-loop-helix region interlinking the AsLOV2-Jα- and TrpR-domains, ultimately enabling the condensation of LOV-TAP onto the DNA surface. By contrast, in the dark state the AsLOV2-Jα photoswitch remains inactive and exerts a repulsive electrostatic force on the DNA surface. This leads to a distortion of the hairpin region, which finally relieves its tension by causing the disruption of LOV-TAP from the DNA.
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Affiliation(s)
- Emanuel Peter
- Department of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, Regensburg D-93040, Germany
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Peter E, Dick B, Baeurle SA. A novel computer simulation method for simulating the multiscale transduction dynamics of signal proteins. J Chem Phys 2012; 136:124112. [DOI: 10.1063/1.3697370] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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Zayner JP, Antoniou C, Sosnick TR. The amino-terminal helix modulates light-activated conformational changes in AsLOV2. J Mol Biol 2012; 419:61-74. [PMID: 22406525 DOI: 10.1016/j.jmb.2012.02.037] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 02/21/2012] [Accepted: 02/24/2012] [Indexed: 01/27/2023]
Abstract
The mechanism of light-triggered conformational change and signaling in light-oxygen-voltage (LOV) domains remains elusive in spite of extensive investigation and their use in optogenetic studies. The LOV2 domain of Avenasativa phototropin 1 (AsLOV2), a member of the Per-Arnt-Sim (PAS) family, contains a flavin mononucleotide chromophore that forms a covalent bond with a cysteine upon illumination. This event leads to the release of the carboxy-terminal Jα helix, the biological output signal. Using mutational analysis, circular dichroism, and NMR, we find that the largely ignored amino-terminal helix is a control element in AsLOV2's light-activated conformational change. We further identify a direct amino-to-carboxy-terminal "input-output" signaling pathway. These findings provide a framework to rationalize the LOV domain architecture, as well as the signaling mechanisms in both isolated and tandem arrangements of PAS domains. This knowledge can be applied in engineering LOV-based photoswitches, opening up new design strategies and improving existing ones.
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Affiliation(s)
- Josiah P Zayner
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
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Peter E, Dick B, Baeurle SA. Signaling pathway of a photoactivable Rac1-GTPase in the early stages. Proteins 2012; 80:1350-62. [DOI: 10.1002/prot.24031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 12/17/2011] [Accepted: 12/29/2011] [Indexed: 12/18/2022]
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Peter E, Dick B, Baeurle SA. Illuminating the early signaling pathway of a fungal light-oxygen-voltage photoreceptor. Proteins 2011; 80:471-81. [PMID: 22081493 DOI: 10.1002/prot.23213] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 09/20/2011] [Accepted: 09/27/2011] [Indexed: 12/20/2022]
Abstract
Circadian clocks are molecular timekeepers encountered in a wide variety of organisms, which allow to adapt the cell's metabolism and behavior to the daily and seasonal periods. Their function is regulated by light-sensing proteins, among which Vivid, a light-oxygen-voltage (LOV) sensitive domain of the fungus Neurospora crassa, constitutes one of the most prominent examples. Although the major photochemical and structural changes during the photocycle of this photosensor have been elucidated through experimental means, its signal transduction pathway is still poorly resolved at the molecular level. In this article, we show through molecular dynamics simulation that the primary steps after adduct formation involve a switch of Gln182 in vicinity of the chromophore FAD (flavin-adenine-dinucleotide), followed by a coupling between the Iβ- and Hβ-strands through H-bond formation between Gln182 and Asn161 as well as subsequent weakening of the H-bonding interaction between the Iβ- and Aβ-strands. These processes then induce a reorientation of the Aβ-Bβ-loop with respect to the protein core as well as a simultaneous contraction of the partially unfolded α-helix onto the α-Aβ-linker at the Ncap. Finally, we demonstrate through additional dimer simulations that the light-induced conformational changes, observed in the monomeric case, play a decisive role in controlling the dimerization tendency of Vivid with its partner domains and that the light-state homodimer shows a much larger affinity for aggregation than the dark state.
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Affiliation(s)
- Emanuel Peter
- Department of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, Regensburg D-93040, Germany
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Peter E, Dick B, Baeurle SA. Signals of LOV1: a computer simulation study on the wildtype LOV1-domain of Chlamydomonas reinhardtii and its mutants. J Mol Model 2011; 18:1375-88. [PMID: 21761179 DOI: 10.1007/s00894-011-1165-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 06/24/2011] [Indexed: 01/12/2023]
Abstract
Phototropins are photoreceptors regulating the blue-light response in plants and bacteria. They consist of two LOV (light oxygen voltage sensitive) domains each containing a non-covalently bound flavin-mononucleotide (FMN) chromophore, which are connected to a serine/threonine-kinase. Upon illumination, the LOV-domains undergo conformational changes, triggering a signal cascade in the organism through kinase activation. Here, we present results from molecular dynamics simulations in which we investigate the signal transduction pathway of the wildtype LOV1-domain of Chlamydomonas reinhardtii and a methyl-mercaptan (MM) adduct of its Cys57Gly-mutant at the molecular level. In particular, we analyzed the effect of covalent-bond formation between the reactive cysteine Cys57 and the FMN-reaction center, as well as the subsequent charge redistribution, on the spatio-dynamical behavior of the LOV1-domain. We compare the calculation results with experimental data and demonstrate that these adduct state characteristics have an important influence on the response of this photosensor. The light-induced changes implicate primarily an alteration of the surface charge distribution through rearrangement of the highly flexible Cα-, Dα- and Eα-helices including the Glu51-Lys91-salt bridge on the hydrophilic side of the protein domain and a β-sheet tightening process via coupling of the Aβ- and Bβ-strands. Our findings confirm the aptitude of the LOV1-domain to function as a dimerization partner, allowing the green alga to adapt its reproduction and growth speed to the environmental conditions.
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Affiliation(s)
- Emanuel Peter
- Department of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
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Peter E, Dick B, Baeurle SA. Effect of computational methodology on the conformational dynamics of the protein photosensor LOV1 from Chlamydomonas reinhardtii. J Chem Biol 2011; 4:167-84. [PMID: 22408688 DOI: 10.1007/s12154-011-0060-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 02/17/2011] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED LOV domains are the light-sensitive protein domains of plant phototropins and bacteria. They photochemically form a covalent bond between a flavin mononucleotide (FMN) chromophore and a cysteine, attached to the apo-protein, upon irradiation with blue light, which triggers a signal in the adjacent kinase. Although their signaling state has been well characterized through experimental means, their signal transduction pathway as well as dark-state activity are generally only poorly understood. Here we show results from molecular dynamics simulations where we investigated the effect of thermostating and long-range electrostatics on the solution structure and dynamical behavior of the wild-type LOV1 domain from the green algae Chlamydomonas reinhardtii in the dark. We demonstrate that these computational issues can dramatically affect the conformational fluctuations of such protein domains by suppressing configurations far from equilibrium or destabilizing local configurations, leading to artificial changes of the protein secondary structure as well as the H-bond network formed by the amino acids and the FMN. By comparing our calculation results with recent experimental data, we show that the non-invasive thermostating strategy, where the protein solute is only indirectly coupled to the thermostat via the solvent, in conjunction with the particle-mesh Ewald technique, provides dark-state conformers, which are in consistency with experimental observations. Moreover, our calculations indicate that the LOV1 domains can alter the intersystem crossing rate and rate of adduct formation by adjusting the population distribution of these dark-state conformers. This might permit them to function as a modulator of the signal intensity under low light conditions. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (doi:10.1007/s12154-011-0060-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Emanuel Peter
- Department of Chemistry and Pharmacy, Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
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