1
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Alves J, Schwinn M, Machleidt T, Goueli SA, Cali JJ, Zegzouti H. Monitoring phosphorylation and acetylation of CRISPR-mediated HiBiT-tagged endogenous proteins. Sci Rep 2024; 14:2138. [PMID: 38272933 PMCID: PMC10810970 DOI: 10.1038/s41598-024-51887-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/10/2024] [Indexed: 01/27/2024] Open
Abstract
Intracellular pathways transduce signals through changes in post-translational modifications (PTMs) of effector proteins. Among the approaches used to monitor PTM changes are immunoassays and overexpression of recombinant reporter genes. Genome editing by CRISPR/Cas9 provides a new means to monitor PTM changes by inserting reporters onto target endogenous genes while preserving native biology. Ideally, the reporter should be small in order not to interfere with the processes mediated by the target while sensitive enough to detect tightly expressed proteins. HiBiT is a 1.3 kDa reporter peptide capable of generating bioluminescence through complementation with LgBiT, an 18 kDa subunit derived from NanoLuc. Using HiBiT CRISPR/Cas9-modified cell lines in combination with fluorescent antibodies, we developed a HiBiT-BRET immunoassay (a.k.a. Immuno-BRET). This is a homogeneous immunoassay capable of monitoring post-translational modifications on diverse protein targets. Its usefulness was demonstrated for the detection of phosphorylation of multiple signaling pathway targets (EGFR, STAT3, MAPK8 and c-MET), as well as chromatin containing histone H3 acetylation on lysine 9 and 27. These results demonstrate the ability to efficiently monitor endogenous biological processes modulated by post-translational modifications using a small bioluminescent peptide tag and fluorescent antibodies, providing sensitive quantitation of the response dynamics to multiple stimuli.
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Affiliation(s)
- Juliano Alves
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA.
| | - Marie Schwinn
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA
| | - Thomas Machleidt
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA
| | - Said A Goueli
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA
| | - James J Cali
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA
| | - Hicham Zegzouti
- R&D Department, Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA.
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2
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Klein MA, Lazarev S, Gervasi C, Cowan C, Machleidt T, Friedman Ohana R. Luciferase Calibrants Enable Absolute Quantitation of Bioluminescence Power. ACS Meas Sci Au 2023; 3:496-503. [PMID: 38145021 PMCID: PMC10740115 DOI: 10.1021/acsmeasuresciau.3c00036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/06/2023] [Accepted: 10/09/2023] [Indexed: 12/26/2023]
Abstract
Bioluminescence emitted from a luciferase-catalyzed oxidation of luciferin has been broadly utilized to report on biological events, predominantly through relative changes in the light output. Recent advances in protein engineering and synthetic chemistry have yielded bioluminescent systems with markedly improved brightness and bioavailability. These developments have enabled not only the detection of biological events at far lower expression levels but also new opportunities utilizing bioluminescence to power photochemistry in cells. Regardless of the application, bioluminescence analyses have leaned heavily on the use of luminometers to measure the light output of a system. Current luminometers report the light output of a sample in relative units, limiting the ability to compare data between instruments and preventing the absolute power of a bioluminescent system from being quantified. Luminescent solution calibrants comprising luciferases and their cognate luciferins that have been characterized for absolute light output would enable calibration of any given luminometer for absolute photon counting. To this end, we have built a custom light detection apparatus and used it alongside wavelength-matched LED light sources emitting at 450 and 561 nm to characterize the absolute power of a series of NanoLuc and firefly luciferase solutions, respectively. This approach revealed that these two common luciferases produce 3.72 × 10-18 and 7.25 × 10-20 watts/molecule, respectively. Components of these luminescent solution calibrants are commercially available and produce stable bioluminescent signals over 2-5 min, enabling any luminometer to be calibrated for power measurements of bioluminescence emitted by these two luciferases in units of watts or photons per second.
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Affiliation(s)
- Mark A. Klein
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Sergey Lazarev
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Charles Gervasi
- Promega Corporation, Madison, Wisconsin 53711, United States
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3
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Wimberger S, Akrap N, Firth M, Brengdahl J, Engberg S, Schwinn MK, Slater MR, Lundin A, Hsieh PP, Li S, Cerboni S, Sumner J, Bestas B, Schiffthaler B, Magnusson B, Di Castro S, Iyer P, Bohlooly-Y M, Machleidt T, Rees S, Engkvist O, Norris T, Cadogan EB, Forment JV, Šviković S, Akcakaya P, Taheri-Ghahfarokhi A, Maresca M. Simultaneous inhibition of DNA-PK and Polϴ improves integration efficiency and precision of genome editing. Nat Commun 2023; 14:4761. [PMID: 37580318 PMCID: PMC10425386 DOI: 10.1038/s41467-023-40344-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 07/25/2023] [Indexed: 08/16/2023] Open
Abstract
Genome editing, specifically CRISPR/Cas9 technology, has revolutionized biomedical research and offers potential cures for genetic diseases. Despite rapid progress, low efficiency of targeted DNA integration and generation of unintended mutations represent major limitations for genome editing applications caused by the interplay with DNA double-strand break repair pathways. To address this, we conduct a large-scale compound library screen to identify targets for enhancing targeted genome insertions. Our study reveals DNA-dependent protein kinase (DNA-PK) as the most effective target to improve CRISPR/Cas9-mediated insertions, confirming previous findings. We extensively characterize AZD7648, a selective DNA-PK inhibitor, and find it to significantly enhance precise gene editing. We further improve integration efficiency and precision by inhibiting DNA polymerase theta (Polϴ). The combined treatment, named 2iHDR, boosts templated insertions to 80% efficiency with minimal unintended insertions and deletions. Notably, 2iHDR also reduces off-target effects of Cas9, greatly enhancing the fidelity and performance of CRISPR/Cas9 gene editing.
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Affiliation(s)
- Sandra Wimberger
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.
- Department of Chemistry & Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
| | - Nina Akrap
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Mike Firth
- Data Sciences & Quantitative Biology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Johan Brengdahl
- Cell Assay Development, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Susanna Engberg
- Cell Engineering Sweden, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | | | | | - Anders Lundin
- Translational Genomics, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Pei-Pei Hsieh
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Songyuan Li
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Silvia Cerboni
- Translational Science & Experimental Medicine, Research and Early Development, Respiratory & Immunology (R&I), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Jonathan Sumner
- Cell Immunology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Burcu Bestas
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Bastian Schiffthaler
- Data Sciences & Quantitative Biology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Björn Magnusson
- Translational Genomics, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Silvio Di Castro
- Compound Synthesis & Management, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Preeti Iyer
- Molecular AI, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Mohammad Bohlooly-Y
- Translational Genomics, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | | | - Steve Rees
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Ola Engkvist
- Molecular AI, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Tyrell Norris
- Cell Engineering Sweden, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | | | | | - Saša Šviković
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Pinar Akcakaya
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Amir Taheri-Ghahfarokhi
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Marcello Maresca
- Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.
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4
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Torio EA, Ressler VT, Kincaid VA, Hurst R, Hall MP, Encell LP, Zimmerman K, Forsyth SK, Rehrauer WM, Accola MA, Hsu CC, Machleidt T, Dart ML. Development of a rapid, simple, and sensitive point-of-care technology platform utilizing ternary NanoLuc. Front Microbiol 2022; 13:970233. [PMID: 36386626 PMCID: PMC9643700 DOI: 10.3389/fmicb.2022.970233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 10/06/2022] [Indexed: 12/02/2022] Open
Abstract
Point-of-care tests are highly valuable in providing fast results for medical decisions for greater flexibility in patient care. Many diagnostic tests, such as ELISAs, that are commonly used within clinical laboratory settings require trained technicians, laborious workflows, and complex instrumentation hindering their translation into point-of-care applications. Herein, we demonstrate the use of a homogeneous, bioluminescent-based, split reporter platform that enables a simple, sensitive, and rapid method for analyte detection in clinical samples. We developed this point-of-care application using an optimized ternary, split-NanoLuc luciferase reporter system that consists of two small reporter peptides added as appendages to analyte-specific affinity reagents. A bright, stable bioluminescent signal is generated as the affinity reagents bind to the analyte, allowing for proximity-induced complementation between the two reporter peptides and the polypeptide protein, in addition to the furimazine substrate. Through lyophilization of the stabilized reporter system with the formulated substrate, we demonstrate a shelf-stable, all-in-one, add-and-read analyte-detection system for use in complex sample matrices at the point-of-care. We highlight the modularity of this platform using two distinct SARS-CoV-2 model systems: SARS-CoV-2 N-antigen detection for active infections and anti-SARS-CoV-2 antibodies for immunity status detection using chemically conjugated or genetically fused affinity reagents, respectively. This technology provides a simple and standardized method to develop rapid, robust, and sensitive analyte-detection assays with flexible assay formatting making this an ideal platform for research, clinical laboratory, as well as point-of-care applications utilizing a simple handheld luminometer.
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Affiliation(s)
| | | | | | - Robin Hurst
- Promega Corporation, Madison, WI, United States
| | - Mary P Hall
- Promega Corporation, Madison, WI, United States
| | | | | | | | - William M Rehrauer
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
- University of Wisconsin Hospital and Clinics, Clinical Laboratories, Madison, WI, United States
| | - Molly A Accola
- University of Wisconsin Hospital and Clinics, Clinical Laboratories, Madison, WI, United States
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5
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Kincaid VA, Wang H, Sondgeroth CA, Torio EA, Ressler VT, Fitzgerald C, Hall MP, Hurst R, Wood MG, Gilden JK, Kirkland TA, Lazar D, Chia-Chang H, Encell LP, Machleidt T, Zhou W, Dart ML. Simple, Rapid Chemical Labeling and Screening of Antibodies with Luminescent Peptides. ACS Chem Biol 2022; 17:2179-2187. [PMID: 35862857 PMCID: PMC9396617 DOI: 10.1021/acschembio.2c00306] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
![]()
Sensitive and selective detection assays are essential
for the
accurate measurement of analytes in both clinical and research laboratories.
Immunoassays that rely on nonoverlapping antibodies directed against
the same target analyte (e.g., sandwich enzyme-linked immunosorbent
assays (ELISAs)) are commonly used molecular detection technologies.
Use of split enzyme reporters has simplified the workflow for these
traditionally complex assays. However, identifying functional antibody
pairs for a given target analyte can be cumbersome, as it generally
involves generating and screening panels of antibodies conjugated
to reporters. Accordingly, we sought a faster and easier reporter
conjugation strategy to streamline antibody screening. We describe
here the development of such a method that is based on an optimized
ternary NanoLuc luciferase. This bioluminescence complementation system
is comprised of a reagent-based thermally stable polypeptide (LgTrip)
and two small peptide tags (β9 and β10) with lysine-reactive
handles for direct conjugation onto antibodies. These reagents enable
fast, single-step, wash-free antibody labeling and sensitive functional
screening. Simplicity, speed, and utility of the one-pot labeling
technology are demonstrated in screening antibody pairs for the analyte
interleukin-4. The screen resulted in the rapid development of a sensitive
homogeneous immunoassay for this clinically relevant cytokine.
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Affiliation(s)
| | - Hui Wang
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | | | - Emily A Torio
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Connor Fitzgerald
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | - Mary P Hall
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Robin Hurst
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Monika G Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Julia K Gilden
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Thomas A Kirkland
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | - Dan Lazar
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Hsu Chia-Chang
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Lance P Encell
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Wenhui Zhou
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | - Melanie L Dart
- Promega Corporation, Madison, Wisconsin 53711, United States
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6
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Killoran MP, Levin S, Boursier ME, Zimmerman K, Hurst R, Hall MP, Machleidt T, Kirkland TA, Friedman Ohana R. An Integrated Approach toward NanoBRET Tracers for Analysis of GPCR Ligand Engagement. Molecules 2021; 26:molecules26102857. [PMID: 34065854 PMCID: PMC8151276 DOI: 10.3390/molecules26102857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 01/22/2023] Open
Abstract
Gaining insight into the pharmacology of ligand engagement with G-protein coupled receptors (GPCRs) under biologically relevant conditions is vital to both drug discovery and basic research. NanoLuc-based bioluminescence resonance energy transfer (NanoBRET) monitoring competitive binding between fluorescent tracers and unmodified test compounds has emerged as a robust and sensitive method to quantify ligand engagement with specific GPCRs genetically fused to NanoLuc luciferase or the luminogenic HiBiT peptide. However, development of fluorescent tracers is often challenging and remains the principal bottleneck for this approach. One way to alleviate the burden of developing a specific tracer for each receptor is using promiscuous tracers, which is made possible by the intrinsic specificity of BRET. Here, we devised an integrated tracer discovery workflow that couples machine learning-guided in silico screening for scaffolds displaying promiscuous binding to GPCRs with a blend of synthetic strategies to rapidly generate multiple tracer candidates. Subsequently, these candidates were evaluated for binding in a NanoBRET ligand-engagement screen across a library of HiBiT-tagged GPCRs. Employing this workflow, we generated several promiscuous fluorescent tracers that can effectively engage multiple GPCRs, demonstrating the efficiency of this approach. We believe that this workflow has the potential to accelerate discovery of NanoBRET fluorescent tracers for GPCRs and other target classes.
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Affiliation(s)
- Michael P. Killoran
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Sergiy Levin
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, CA 93401, USA; (S.L.); (T.A.K.)
| | - Michelle E. Boursier
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Kristopher Zimmerman
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Robin Hurst
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Mary P. Hall
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
| | - Thomas A. Kirkland
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, CA 93401, USA; (S.L.); (T.A.K.)
| | - Rachel Friedman Ohana
- Promega Corporation, 2800 Woods Hollow, Fitchburg, WI 53711, USA; (M.P.K.); (M.E.B.); (K.Z.); (R.H.); (M.P.H.); (T.M.)
- Correspondence: ; Tel.: +1-608-274-1181
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7
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Hall MP, Kincaid VA, Jost EA, Smith TP, Hurst R, Forsyth SK, Fitzgerald C, Ressler VT, Zimmermann K, Lazar D, Wood MG, Wood KV, Kirkland TA, Encell LP, Machleidt T, Dart ML. Toward a Point-of-Need Bioluminescence-Based Immunoassay Utilizing a Complete Shelf-Stable Reagent. Anal Chem 2021; 93:5177-5184. [PMID: 33730483 DOI: 10.1021/acs.analchem.0c05074] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Enzyme-linked immunosorbent assays (ELISAs) are used extensively for the detection and quantification of biomolecules in clinical diagnostics as well as in basic research. Although broadly used, the inherent complexities of ELISAs preclude their utility for straightforward point-of-need testing, where speed and simplicity are essential. With this in mind, we developed a bioluminescence-based immunoassay format that provides a sensitive and simple method for detecting biomolecules in clinical samples. We utilized a ternary, split-NanoLuc luciferase complementation reporter consisting of two small peptides (11mer, 13mer) and a 17 kDa polypeptide combined with a luminogenic substrate to create a complete, shelf-stable add-and-read assay detection reagent. Directed evolution was used to optimize reporter constituent sequences to impart chemical and thermal stability, as well as solubility, while formulation optimization was applied to stabilize an all-in-one reagent that can be reconstituted in aqueous buffers or sample matrices. The result of these efforts is a robust, first-generation bioluminescence-based homogenous immunoassay reporter platform where all assay components can be configured into a stable lyophilized cake, supporting homogeneous, rapid, and sensitive one-step biomolecule quantification in complex human samples. This technology represents a promising alternative immunoassay format with significant potential to bring critical diagnostic molecular detection testing closer to the point-of-need.
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Affiliation(s)
- Mary P Hall
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Emily A Jost
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Thomas P Smith
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | - Robin Hurst
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Connor Fitzgerald
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | | | - Kris Zimmermann
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Dan Lazar
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Monika G Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Keith V Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Thomas A Kirkland
- Promega Biosciences LLC, San Luis Obispo, California 93401, United States
| | - Lance P Encell
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Melanie L Dart
- Promega Corporation, Madison, Wisconsin 53711, United States
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8
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Friedman Ohana R, Levin S, Hurst R, Rosenblatt MM, Zimmerman K, Machleidt T, Wood KV, Kirkland TA. Streamlined Target Deconvolution Approach Utilizing a Single Photoreactive Chloroalkane Capture Tag. ACS Chem Biol 2021; 16:404-413. [PMID: 33543920 DOI: 10.1021/acschembio.0c00987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Identification of physiologically relevant targets for lead compounds emerging from drug discovery screens is often the rate-limiting step toward understanding their mechanism of action and potential for undesired off-target effects. To this end, we developed a streamlined chemical proteomic approach utilizing a single, photoreactive cleavable chloroalkane capture tag, which upon attachment to bioactive compounds facilitates selective isolation of their respective cellular targets for subsequent identification by mass spectrometry. When properly positioned, the tag does not significantly affect compound potency and membrane permeability, allowing for binding interactions with the tethered compound (probe) to be established within intact cells under physiological conditions. Subsequent UV-induced covalent photo-cross-linking "freezes" the interactions between the probe and its cellular targets and prevents their dissociation upon cell lysis. Targets cross-linked to the capture tag are then efficiently enriched through covalent capture onto HaloTag coated beads and subsequent selective chemical release from the solid support. The tag's built-in capability for selective enrichment eliminates the need for ligation of a capture tag, thereby simplifying the workflow and reducing variability introduced through additional operational steps. At the same time, the capacity for adequate cross-linking without structural optimization permits modular assembly of photoreactive chloroalkane probes, which reduces the burden of customized chemistry. Using three model compounds, we demonstrate the capability of this approach to identify known and novel cellular targets, including those with low affinity and/or low abundance as well as membrane targets with several transmembrane domains.
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Affiliation(s)
| | - Sergiy Levin
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, California 93401, United States
| | - Robin Hurst
- Promega Corporation, 2800 Woods Hollow, Fitchburg, Wisconsin 53711, United States
| | | | - Kristopher Zimmerman
- Promega Corporation, 2800 Woods Hollow, Fitchburg, Wisconsin 53711, United States
| | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow, Fitchburg, Wisconsin 53711, United States
| | - Keith V. Wood
- Promega Corporation, 2800 Woods Hollow, Fitchburg, Wisconsin 53711, United States
| | - Thomas A. Kirkland
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, California 93401, United States
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9
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Shi C, Killoran MP, Hall MP, Otto P, Wood MG, Strauss E, Encell LP, Machleidt T, Wood KV, Kirkland TA. 5,5-Dialkylluciferins are thermal stable substrates for bioluminescence-based detection systems. PLoS One 2020; 15:e0243747. [PMID: 33315907 PMCID: PMC7735563 DOI: 10.1371/journal.pone.0243747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/26/2020] [Indexed: 11/18/2022] Open
Abstract
Firefly luciferase-based ATP detection assays are frequently used as a sensitive, cost-efficient method for monitoring hygiene in many industrial settings. Solutions of detection reagent, containing a mixture of a substrate and luciferase enzyme that produces photons in the presence of ATP, are relatively unstable and maintain only a limited shelf life even under refrigerated conditions. It is therefore common for the individual performing a hygiene test to manually prepare fresh reagent at the time of monitoring. To simplify sample processing, a liquid detection reagent with improved thermal stability is needed. The engineered firefly luciferase, Ultra-Glo™, fulfills one aspect of this need and has been valuable for hygiene monitoring because of its high resistance to chemical and thermal inactivation. However, solutions containing both Ultra-Glo™ luciferase and its substrate luciferin gradually lose the ability to effectively detect ATP over time. We demonstrate here that dehydroluciferin, a prevalent oxidative breakdown product of luciferin, is a potent inhibitor of Ultra-Glo™ luciferase and that its formation in the detection reagent is responsible for the decreased ability to detect ATP. We subsequently found that dialkylation at the 5-position of luciferin (e.g., 5,5-dimethylluciferin) prevents degradation to dehydroluciferin and improves substrate thermostability in solution. However, since 5,5-dialkylluciferins are poorly utilized by Ultra-Glo™ luciferase as substrates, we used structural optimization of the luciferin dialkyl modification and protein engineering of Ultra-Glo™ to develop a luciferase/luciferin pair that shows improved total reagent stability in solution at ambient temperature. The results of our studies outline a novel luciferase/luciferin system that could serve as foundations for the next generation of bioluminescence ATP detection assays with desirable reagent stability.
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Affiliation(s)
- Ce Shi
- Promega Biosciences, Inc., San Luis Obispo, California, United States of America
| | | | - Mary P. Hall
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Paul Otto
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Monika G. Wood
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Ethan Strauss
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Lance P. Encell
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Thomas Machleidt
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Keith V. Wood
- Promega Corporation, Madison, Wisconsin, United States of America
| | - Thomas A. Kirkland
- Promega Biosciences, Inc., San Luis Obispo, California, United States of America
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10
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Riching KM, Schwinn MK, Vasta JD, Robers MB, Machleidt T, Urh M, Daniels DL. CDK Family PROTAC Profiling Reveals Distinct Kinetic Responses and Cell Cycle-Dependent Degradation of CDK2. SLAS Discov 2020; 26:560-569. [PMID: 33190579 DOI: 10.1177/2472555220973602] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Targeted protein degradation using heterobifunctional proteolysis-targeting chimera (PROTAC) compounds, which recruit E3 ligase machinery to a target protein, is increasingly becoming an attractive pharmacologic strategy. PROTAC compounds are often developed from existing inhibitors, and assessing selectivity is critical for understanding on-target and off-target degradation. We present here an in-depth kinetic degradation study of the pan-kinase PROTAC, TL12-186, applied to 16 members of the cyclin-dependent kinase (CDK) family. Each CDK family member was endogenously tagged with the 11-amino-acid HiBiT peptide, allowing for live cell luminescent monitoring of degradation. Using this approach, we found striking differences and patterns in kinetic degradation rates, potencies, and Dmax values across the CDK family members. Analysis of the responses revealed that most of the CDKs showed rapid and near complete degradation, yet all cell cycle-associated CDKs (1, 2, 4, and 6) showed multimodal and partial degradation. Further mechanistic investigation of the key cell cycle protein CDK2 was performed and revealed CDK2 PROTAC-dependent degradation in unsynchronized or G1-arrested cells but minimal loss in S or G2/M arrest. The ability of CDK2 to form the PROTAC-mediated ternary complex with CRBN in only G1-arrested cells matched these trends, despite binding of CDK2 to TL12-186 in all phases. These data indicate that target subpopulation degradation can occur, dictated by the formation of the ternary complex. These studies additionally underscore the importance of profiling degradation compounds in cellular systems where complete pathways are intact and target proteins can be characterized in their relevant complexes.
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11
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Vasta J, Wells C, Corona C, Wilkinson J, Zimprich C, Ingold M, Ogno D, Schwinn M, Machleidt T, Cong M, Fan F, Huwiler K, Landreman A, Pickett JE, Huber K, Robers M. Abstract 5808: Examination of clinically relevant inhibitor selectivity in live cells across the CDK family. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-5808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cyclin-dependent kinases (CDK) play key roles in diverse cellular functions including cell cycle control, cell proliferation, and transcriptional regulation. Due to these important roles, CDKs have been targeted for cancer therapeutic development, which has resulted in hundreds of small molecule inhibitors. However, conflicting data of CDK inhibitor potency has been reported and a rigorous comparison of inhibitor affinity and selectivity for intracellular CDKs is lacking. To address this need, we have developed a panel of cell-permeable energy transfer probes or tracers to enable comprehensive quantitation of inhibitor target occupancy and affinity for CDKs in live cells via a bioluminescent energy transfer (BRET) method. Specifically, the quantitative BRET-based capability is achieved via energy transfer from cell-permeable fluorescent tracers reversibly engaged to NanoLuc luciferase-tagged CDK proteins expressed in live cells. An untagged cyclin can be introduced into the cells at the same time as the NanoLuc-CDK, allowing for the interrogation of a specific CDK-cyclin pair. The BRET-based method can be used in equilibrium binding analysis. In addition, time-dependent target-compound occupancy (or residence time) can also be obtained with this method. We will present a comprehensive evaluation of intracellular isozyme potency and selectivity for a collection of clinically-advanced CDK inhibitors and chemical probes across the CDK family. We observed unexpected intracellular activity profiles for some clinically-advanced CDK inhibitors. We further evaluated mechanisms for achieving target selectivity through target residence time under non-equilibrium cell culture conditions. This BRET-based method is broadly applicable for evaluating the occupancy, affinity, and selectivity of chemical matter for CDKs in live cells.
Citation Format: James Vasta, Carrow Wells, Cesear Corona, Jennifer Wilkinson, Chad Zimprich, Morgan Ingold, Domenic Ogno, Marie Schwinn, Thomas Machleidt, Mei Cong, Frank Fan, Kristin Huwiler, Amy Landreman, Julie E. Pickett, Kilian Huber, Matthew Robers. Examination of clinically relevant inhibitor selectivity in live cells across the CDK family [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5808.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Mei Cong
- 1Promega Corporation, Madison, WI
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12
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Vasta J, Corona C, Wilkinson J, Ingold MR, Zimprich C, Schwinn M, Machleidt T, Hartnett J, Cong M, Fan F, Somberg RL, Robers M. Abstract 6407: A live cell method to assess E3 ligase and target protein occupancy for PROTACs. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-6407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Proteolysis targeting chimeras (PROTACs) are bifunctional molecules that hijack ubiquitin E3 ligases and induce degradation of intracellular proteins through a tightly regulated proteosomal mechanism. Although several successful PROTACs have been developed against key intracellular target classes including bromodomains, kinases, and nuclear hormone receptors, these bivalent molecules often suffer from poor cell permeability due to high molecular weight. To enable a high-throughput, quantitative readout for PROTAC permeability and E3 ligase occupancy in living cells, we have developed a panel of target engagement (TE) assays for key E3 ligase including CRBN, VHL, XIAP, cIAP, and MDM2. These intracellular assays are the first biophysical method to enable the quantitative determination of compound occupancy, potency, and residence time for specific target proteins inside living cells. The assays provide a direct measure of compound binding or occupancy to a target under physiological conditions using bioluminescent resonance energy transfer (BRET).
Citation Format: James Vasta, Cesear Corona, Jennifer Wilkinson, Morgan R. Ingold, Chad Zimprich, Marie Schwinn, Thomas Machleidt, Jim Hartnett, Mei Cong, Frank Fan, Richard L. Somberg, Matthew Robers. A live cell method to assess E3 ligase and target protein occupancy for PROTACs [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6407.
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13
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Schwinn MK, Steffen LS, Zimmerman K, Wood KV, Machleidt T. A Simple and Scalable Strategy for Analysis of Endogenous Protein Dynamics. Sci Rep 2020; 10:8953. [PMID: 32488146 PMCID: PMC7265437 DOI: 10.1038/s41598-020-65832-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 05/08/2020] [Indexed: 11/20/2022] Open
Abstract
The ability to analyze protein function in a native context is central to understanding cellular physiology. This study explores whether tagging endogenous proteins with a reporter is a scalable strategy for generating cell models that accurately quantitate protein dynamics. Specifically, it investigates whether CRISPR-mediated integration of the HiBiT luminescent peptide tag can easily be accomplished on a large-scale and whether integrated reporter faithfully represents target biology. For this purpose, a large set of proteins representing diverse structures and functions, some of which are known or potential drug targets, were targeted for tagging with HiBiT in multiple cell lines. Successful insertion was detected for 86% of the targets, as determined by luminescence-based plate assays, blotting, and imaging. In order to determine whether endogenously tagged proteins yield more representative models, cells expressing HiBiT protein fusions either from endogenous loci or plasmids were directly compared in functional assays. In the tested cases, only the edited lines were capable of accurately reproducing the anticipated biology. This study provides evidence that cell lines expressing HiBiT fusions from endogenous loci can be rapidly generated for many different proteins and that these cellular models provide insight into protein function that may be unobtainable using overexpression-based approaches.
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Affiliation(s)
- Marie K Schwinn
- Promega Corporation, Madison, Wisconsin, 53711, United States.
| | - Leta S Steffen
- Promega Corporation, Madison, Wisconsin, 53711, United States
| | - Kris Zimmerman
- Promega Corporation, Madison, Wisconsin, 53711, United States
| | - Keith V Wood
- Light Bio, Inc., Madison, Wisconsin, 53711, United States
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14
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Boursier ME, Levin S, Zimmerman K, Machleidt T, Hurst R, Butler BL, Eggers CT, Kirkland TA, Wood KV, Friedman Ohana R. The luminescent HiBiT peptide enables selective quantitation of G protein-coupled receptor ligand engagement and internalization in living cells. J Biol Chem 2020; 295:5124-5135. [PMID: 32107310 DOI: 10.1074/jbc.ra119.011952] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/18/2020] [Indexed: 01/19/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are prominent targets to new therapeutics for a range of diseases. Comprehensive assessments of their cellular interactions with bioactive compounds, particularly in a kinetic format, are imperative to the development of drugs with improved efficacy. Hence, we developed complementary cellular assays that enable equilibrium and real-time analyses of GPCR ligand engagement and consequent activation, measured as receptor internalization. These assays utilize GPCRs genetically fused to an N-terminal HiBiT peptide (1.3 kDa), which produces bright luminescence upon high-affinity complementation with LgBiT, an 18-kDa subunit derived from NanoLuc. The cell impermeability of LgBiT limits signal detection to the cell surface and enables measurements of ligand-induced internalization through changes in cell-surface receptor density. In addition, bioluminescent resonance energy transfer is used to quantify dynamic interactions between ligands and their cognate HiBiT-tagged GPCRs through competitive binding with fluorescent tracers. The sensitivity and dynamic range of these assays benefit from the specificity of bioluminescent resonance energy transfer and the high signal intensity of HiBiT/LgBiT without background luminescence from receptors present in intracellular compartments. These features allow analyses of challenging interactions having low selectivity or affinity and enable studies using endogenously tagged receptors. Using the β-adrenergic receptor family as a model, we demonstrate the versatility of these assays by utilizing the same HiBiT construct in analyses of multiple aspects of GPCR pharmacology. We anticipate that this combination of target engagement and proximal functional readout will prove useful to the study of other GPCR families and the development of new therapeutics.
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Affiliation(s)
| | - Sergiy Levin
- Promega Biosciences LLC, San Luis Obispo, California 93401
| | | | | | - Robin Hurst
- Promega Corporation, Fitchburg, Wisconsin 53711
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15
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Wagner FF, Benajiba L, Campbell AJ, Weïwer M, Sacher JR, Gale JP, Ross L, Puissant A, Alexe G, Conway A, Back M, Pikman Y, Galinsky I, DeAngelo DJ, Stone RM, Kaya T, Shi X, Robers MB, Machleidt T, Wilkinson J, Hermine O, Kung A, Stein AJ, Lakshminarasimhan D, Hemann MT, Scolnick E, Zhang YL, Pan JQ, Stegmaier K, Holson EB. Exploiting an Asp-Glu "switch" in glycogen synthase kinase 3 to design paralog-selective inhibitors for use in acute myeloid leukemia. Sci Transl Med 2019. [PMID: 29515000 DOI: 10.1126/scitranslmed.aam8460] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Glycogen synthase kinase 3 (GSK3), a key regulatory kinase in the wingless-type MMTV integration site family (WNT) pathway, is a therapeutic target of interest in many diseases. Although dual GSK3α/β inhibitors have entered clinical trials, none has successfully translated to clinical application. Mechanism-based toxicities, driven in part by the inhibition of both GSK3 paralogs and subsequent β-catenin stabilization, are a concern in the translation of this target class because mutations and overexpression of β-catenin are associated with many cancers. Knockdown of GSK3α or GSK3β individually does not increase β-catenin and offers a conceptual resolution to targeting GSK3: paralog-selective inhibition. However, inadequate chemical tools exist. The design of selective adenosine triphosphate (ATP)-competitive inhibitors poses a drug discovery challenge due to the high homology (95% identity and 100% similarity) in this binding domain. Taking advantage of an Asp133→Glu196 "switch" in their kinase hinge, we present a rational design strategy toward the discovery of paralog-selective GSK3 inhibitors. These GSK3α- and GSK3β-selective inhibitors provide insights into GSK3 targeting in acute myeloid leukemia (AML), where GSK3α was identified as a therapeutic target using genetic approaches. The GSK3α-selective compound BRD0705 inhibits kinase function and does not stabilize β-catenin, mitigating potential neoplastic concerns. BRD0705 induces myeloid differentiation and impairs colony formation in AML cells, with no apparent effect on normal hematopoietic cells. Moreover, BRD0705 impairs leukemia initiation and prolongs survival in AML mouse models. These studies demonstrate feasibility of paralog-selective GSK3α inhibition, offering a promising therapeutic approach in AML.
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Affiliation(s)
- Florence F Wagner
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA.
| | - Lina Benajiba
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA.,INSERM U1163 and CNRS 8254, Imagine Institute, Université Paris Saclay, 91190 Paris, France
| | - Arthur J Campbell
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Michel Weïwer
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Joshua R Sacher
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Jennifer P Gale
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Linda Ross
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alexandre Puissant
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA.,INSERM U944, Institute of Hematology, St. Louis Hospital, 75010 Paris, France
| | - Gabriela Alexe
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA.,Bioinformatics Graduate Program, Boston University, Boston, MA 02215, USA
| | - Amy Conway
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Morgan Back
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Yana Pikman
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Ilene Galinsky
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Daniel J DeAngelo
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Richard M Stone
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Taner Kaya
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Xi Shi
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Matthew B Robers
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI 53711, USA
| | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI 53711, USA
| | | | - Olivier Hermine
- INSERM U1163 and CNRS 8254, Imagine Institute, Université Sorbonne Paris Cité, Paris, France.,Department of Hematology, Hôpital Necker, Assistance Publique Hôpitaux de Paris, University Paris Descartes, 75006 Paris, France
| | - Andrew Kung
- Department of Pediatrics, Columbia University Medical Center, New York, NY 10032, USA
| | | | | | - Michael T Hemann
- Koch Institute for Integrative Cancer Research at MIT, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Edward Scolnick
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Yan-Ling Zhang
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Kimberly Stegmaier
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA. .,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.,Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Edward B Holson
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
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16
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Friedman Ohana R, Hurst R, Rosenblatt M, Levin S, Machleidt T, Kirkland TA, Encell LP, Robers MB, Wood KV. Utilizing a Simple Method for Stoichiometric Protein Labeling to Quantify Antibody Blockade. Sci Rep 2019; 9:7046. [PMID: 31065015 PMCID: PMC6504924 DOI: 10.1038/s41598-019-43469-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 04/23/2019] [Indexed: 12/13/2022] Open
Abstract
Ligand binding assays routinely employ fluorescently-labeled protein ligands to quantify the extent of binding. These ligands are commonly generated through chemical modification of accessible lysine residues, which often results in heterogeneous populations exhibiting variable binding properties. This could be remedied by quantitative, site-specific labeling. Recently, we reported on a single-step method integrating recombinant protein purification with 2-cyanobenzothiazole (CBT) condensation for labeling a proteolytically exposed N-terminal cysteine. Here, using three growth factors, we show that unlike random lysine labeling, this site-specific approach yielded homogeneous populations of growth factors that were quantitatively labeled at their N-termini and retained their binding characteristics. We demonstrate the utility of this labeling method through the development of a novel assay that quantifies the capacity of antibodies to block receptor-ligand interactions (i.e. antibody blockade). The assay uses bioluminescence resonance energy transfer (BRET) to detect binding of CBT-labeled growth factors to their cognate receptors genetically fused to NanoLuc luciferase. The ability of antibodies to block these interactions is quantified through decrease in BRET. Using several antibodies, we show that the assay provides reliable quantification of antibody blockade in a cellular context. As demonstrated here, this simple method for generating uniformly-labeled proteins has potential to promote more accurate and robust ligand binding assays.
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Affiliation(s)
| | - Robin Hurst
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
| | - Mike Rosenblatt
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
| | - Sergiy Levin
- Promega Biosciences LLC, 277 Granada Dr, San Luis Obispo, CA, 93401, USA
| | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
| | - Thomas A Kirkland
- Promega Biosciences LLC, 277 Granada Dr, San Luis Obispo, CA, 93401, USA
| | - Lance P Encell
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
| | - Matthew B Robers
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
| | - Keith V Wood
- Promega Corporation, 2800 Woods Hollow Rd, Madison, WI, 53711, USA
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17
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Dart ML, Machleidt T, Jost E, Schwinn MK, Robers MB, Shi C, Kirkland TA, Killoran MP, Wilkinson JM, Hartnett JR, Zimmerman K, Wood KV. Homogeneous Assay for Target Engagement Utilizing Bioluminescent Thermal Shift. ACS Med Chem Lett 2018; 9:546-551. [PMID: 29937980 PMCID: PMC6004564 DOI: 10.1021/acsmedchemlett.8b00081] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 04/16/2018] [Indexed: 12/16/2022] Open
Abstract
Protein thermal shift assays (TSAs) provide a means for characterizing target engagement through ligand-induced thermal stabilization. Although these assays are widely utilized for screening libraries and validating hits in drug discovery programs, they can impose encumbering operational requirements, such as the availability of purified proteins or selective antibodies. Appending the target protein with a small luciferase (NanoLuc) allows coupling of thermal denaturation with luminescent output, providing a rapid and sensitive means for assessing target engagement in compositionally complex environments such as permeabilized cells. The intrinsic thermal stability of NanoLuc is greater than mammalian proteins, and our results indicate that the appended luciferase does not alter thermal denaturation of the target protein. We have successfully applied the NanoLuc luciferase thermal shift assay (NaLTSA) to several clinically relevant protein families, including kinases, bromodomains, and histone deacetylases. We have also demonstrated the suitability of this assay method for library screening and compound profiling.
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Affiliation(s)
- Melanie L. Dart
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Thomas Machleidt
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Emily Jost
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Marie K. Schwinn
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Matthew B. Robers
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Ce Shi
- Promega
Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, California 93401, United States
| | - Thomas A. Kirkland
- Promega
Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, California 93401, United States
| | - Michael P. Killoran
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Jennifer M. Wilkinson
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - James R. Hartnett
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Kristopher Zimmerman
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
| | - Keith V. Wood
- Promega
Corporation, 2800 Woods Hollow Road, Madison, Wisconsin 53711, United States
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18
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Shakhmin A, Hall MP, Machleidt T, Walker JR, Wood KV, Kirkland TA. Coelenterazine analogues emit red-shifted bioluminescence with NanoLuc. Org Biomol Chem 2018; 15:8559-8567. [PMID: 28972606 DOI: 10.1039/c7ob01985h] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We report the synthesis and characterization of novel coelenterazine analogues that demonstrate a red-shift in their bioluminescent emission with NanoLuc luciferase. These coelenterazines can be tuned to shift the bioluminescent emission from blue light in the native system. In particular, direct attachment of an aryl moiety to the imidazopyrazinone core of furimazine at the C8 position provides a significant red-shift while maintaining reasonable light output. In addition, modification of the C6 aryl moiety provided additive red-shifts, and by combining the most promising modifications we report a coelenterazine with a maximum emission near 600 nm with NanoLuc. Finally, we show that this new bioluminescent system is capable of efficient BRET to far-red fluorophores. We anticipate these new principles of NanoLuc substrate design will impact applications that depend on shifting the colour of emission to the red, most notably in vivo bioluminescent imaging.
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Affiliation(s)
- Anton Shakhmin
- Promega Biosciences LLC, 277 Granada Dr., San Luis Obispo, CA 93401, USA.
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19
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Schwinn MK, Machleidt T, Zimmerman K, Eggers CT, Dixon AS, Hurst R, Hall MP, Encell LP, Binkowski BF, Wood KV. CRISPR-Mediated Tagging of Endogenous Proteins with a Luminescent Peptide. ACS Chem Biol 2018; 13:467-474. [PMID: 28892606 DOI: 10.1021/acschembio.7b00549] [Citation(s) in RCA: 208] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Intracellular signaling pathways are mediated by changes in protein abundance and post-translational modifications. A common approach for investigating signaling mechanisms and the effects induced by synthetic compounds is through overexpression of recombinant reporter genes. Genome editing with CRISPR/Cas9 offers a means to better preserve native biology by appending reporters directly onto the endogenous genes. An optimal reporter for this purpose would be small to negligibly influence intracellular processes, be readily linked to the endogenous genes with minimal experimental effort, and be sensitive enough to detect low expressing proteins. HiBiT is a 1.3 kDa peptide (11 amino acids) capable of producing bright and quantitative luminescence through high affinity complementation (KD = 700 pM) with an 18 kDa subunit derived from NanoLuc (LgBiT). Using CRISPR/Cas9, we demonstrate that HiBiT can be rapidly and efficiently integrated into the genome to serve as a reporter tag for endogenous proteins. Without requiring clonal isolation of the edited cells, we were able to quantify changes in abundance of the hypoxia inducible factor 1A (HIF1α) and several of its downstream transcriptional targets in response to various stimuli. In combination with fluorescent antibodies, we further used HiBiT to directly correlate HIF1α levels with the hydroxyproline modification that mediates its degradation. These results demonstrate the ability to efficiently tag endogenous proteins with a small luminescent peptide, allowing sensitive quantitation of the response dynamics in their regulated expression and covalent modifications.
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Affiliation(s)
| | | | - Kris Zimmerman
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Andrew S. Dixon
- Department
of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake
City, Utah 84112, United States
| | - Robin Hurst
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Mary P. Hall
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Lance P. Encell
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Keith V. Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
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20
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Vasta JD, Corona CR, Wilkinson J, Zimprich CA, Hartnett JR, Ingold MR, Zimmerman K, Machleidt T, Kirkland TA, Huwiler KG, Ohana RF, Slater M, Otto P, Cong M, Wells CI, Berger BT, Hanke T, Glas C, Ding K, Drewry DH, Huber KVM, Willson TM, Knapp S, Müller S, Meisenheimer PL, Fan F, Wood KV, Robers MB. Quantitative, Wide-Spectrum Kinase Profiling in Live Cells for Assessing the Effect of Cellular ATP on Target Engagement. Cell Chem Biol 2018; 25:206-214.e11. [PMID: 29174542 PMCID: PMC5814754 DOI: 10.1016/j.chembiol.2017.10.010] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/24/2017] [Accepted: 10/24/2017] [Indexed: 02/03/2023]
Abstract
For kinase inhibitors, intracellular target selectivity is fundamental to pharmacological mechanism. Although a number of acellular techniques have been developed to measure kinase binding or enzymatic inhibition, such approaches can fail to accurately predict engagement in cells. Here we report the application of an energy transfer technique that enabled the first broad-spectrum, equilibrium-based approach to quantitatively profile target occupancy and compound affinity in live cells. Using this method, we performed a selectivity profiling for clinically relevant kinase inhibitors against 178 full-length kinases, and a mechanistic interrogation of the potency offsets observed between cellular and biochemical analysis. For the multikinase inhibitor crizotinib, our approach accurately predicted cellular potency and revealed improved target selectivity compared with biochemical measurements. Due to cellular ATP, a number of putative crizotinib targets are unexpectedly disengaged in live cells at a clinically relevant drug dose.
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Affiliation(s)
- James D Vasta
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Cesear R Corona
- Promega Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, CA 93401, USA
| | | | - Chad A Zimprich
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - James R Hartnett
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Morgan R Ingold
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | | | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Thomas A Kirkland
- Promega Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, CA 93401, USA
| | - Kristin G Huwiler
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | | | - Michael Slater
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Paul Otto
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Mei Cong
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Carrow I Wells
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Benedict-Tilman Berger
- Structural Genomics Consortium, Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 9, 60438 Frankfurt am Main, Germany; Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 15, 60438 Frankfurt am Main, Germany
| | - Thomas Hanke
- Structural Genomics Consortium, Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 9, 60438 Frankfurt am Main, Germany
| | - Carina Glas
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Oxford, UK; Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Ke Ding
- State Key Laboratory of Respiratory Diseases, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 190 Kaiyuan Avenue, Guangzhou 510530, China; School of Pharmacy, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, China
| | - David H Drewry
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kilian V M Huber
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Oxford, UK; Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Timothy M Willson
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Stefan Knapp
- Structural Genomics Consortium, Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 9, 60438 Frankfurt am Main, Germany; Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 15, 60438 Frankfurt am Main, Germany
| | - Susanne Müller
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Johann Wolfgang Goethe-University, Max-von-Laue-Straße 15, 60438 Frankfurt am Main, Germany
| | | | - Frank Fan
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Keith V Wood
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA
| | - Matthew B Robers
- Promega Corporation, 2800 Woods Hollow Road, Fitchburg, WI 53711, USA.
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21
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Schwinn MK, Machleidt T, Binkowski BF, Eggers CT, Wood KV. Abstract 4517: A CRISPR approach to monitoring hypoxia-inducible proteins in real-time. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Hypoxia-inducible factor 1A (HIF1A) regulates expression of genes implicated in various aspects of oncogenesis, including angiogenesis, cell survival, metastasis, and glucose metabolism. Overexpression or hypoxia-induced stabilization of HIF1A has been associated with poor prognosis in cancer patients, making HIF1A and its associated pathway a high-profile target for anticancer therapies. We sought to develop a live-cell assay to monitor abundance of endogenous HIF1A and HIF1A-inducible proteins that could be used to identify potent and specific inhibitors of the hypoxia signaling pathway. To accomplish this goal, mammalian cell lines were edited by CRISPR using a Cas9:crRNA ribonucleoprotein complex with a single-stranded oligonucleotide donor DNA to introduce the HiBiT tag at the C-terminus of HIF1A and a number of known hypoxia-inducible proteins, including BNIP3, ANKRD37, HILDPA and KLF10. The 11 amino acid HiBiT peptide and its complementing 18 kDa polypeptide, known as LgBiT, spontaneously reconstitute into an active luciferase derived from the NanoLuc enzyme. Co-expression of LgBiT in edited cells, followed by addition of the cell-permeable luciferase substrate, leads to generation of a bright, steady luminescent signal that directly correlates with abundance of the HiBiT fusion. The edited cells were treated with several known modulators of the HIF1A signaling pathway, and changes in the abundance of the protein fusions were followed in real-time by monitoring luminescence. The HiBiT tag was also used to validate size and subcellular localization of the fusion proteins using bioluminescence imaging and antibody-free blotting. As expected, all tested compounds induced HIF1A accumulation. However, the downstream targets of HIF1A generated differing response to the chemical modulators, warranting further investigation into the modes by which these compounds act. By coupling the speed and efficiency of CRISPR-mediated editing with the small size and brightness of HiBiT, it was possible to generate a live-cell assay to monitor abundance of proteins along the HIF1A pathway. This assay could easily be adapted to screen for compound-induced effects on protein levels of HIF1A, as well as HIF1A- induced changes in expression patterns.
Citation Format: Marie K. Schwinn, Thomas Machleidt, Brock F. Binkowski, Christopher T. Eggers, Keith V. Wood. A CRISPR approach to monitoring hypoxia-inducible proteins in real-time [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4517. doi:10.1158/1538-7445.AM2017-4517
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22
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Duellman SJ, Machleidt T, Cali JJ, Vidugiriene J. Cell-based, bioluminescent assay for monitoring the interaction between PCSK9 and the LDL receptor. J Lipid Res 2017; 58:1722-1729. [PMID: 28611099 PMCID: PMC5538273 DOI: 10.1194/jlr.d074658] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 05/24/2017] [Indexed: 12/12/2022] Open
Abstract
Monitoring the expression of cell-surface receptors, their interaction with extracellular ligands, and their fate upon ligand binding is important for understanding receptor function and developing new therapies. We describe a cell-based method that utilizes bioluminescent protein complementation technology to interrogate binding of a cellular receptor with its extracellular protein ligand, specifically LDL receptor (LDLR) and proprotein convertase subtilisin/kexin type 9 (PCSK9). Purified, full-length tagged PCSK9 is added to assay wells containing cells that stably express LDLR with an extracellular complementary tag. When the tagged PCSK9 binds the receptor, a bright luminescence signal is generated. The interaction is detected at the cell membrane with add-and-read simplicity, no wash steps, and flexibility, allowing data to be collected in endpoint format, kinetically, or with bioluminescent imaging. The assay is flexible, is rapid, and reports accurate biology. It is amenable to 96-well and 384-well formats, and the robustness allows for screening of new drug candidates (Z′ = 0.83). The assay reports correct potencies for antibody titrations across a 50%–150% potency range and detects potency changes due to heat stress, suggesting that it may be useful during drug development. This assay technology can be broadly applied when studying other receptors with their extracellular ligands, whether protein or small-molecule binding partners.
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Walker JR, Hall MP, Zimprich CA, Robers MB, Duellman SJ, Machleidt T, Rodriguez J, Zhou W. Highly Potent Cell-Permeable and Impermeable NanoLuc Luciferase Inhibitors. ACS Chem Biol 2017; 12:1028-1037. [PMID: 28195704 DOI: 10.1021/acschembio.6b01129] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Novel engineered NanoLuc (Nluc) luciferase being smaller, brighter, and superior to traditional firefly (Fluc) or Renilla (Rluc) provides a great opportunity for the development of numerous biological, biomedical, clinical, and food and environmental safety applications. This new platform created an urgent need for Nluc inhibitors that could allow selective bioluminescent suppression and multiplexing compatibility with existing luminescence or fluorescence assays. Starting from thienopyrrole carboxylate 1, a hit from a 42 000 PubChem compound library with a low micromolar IC50 against Nluc, we derivatized four different structural fragments to discover a family of potent, single digit nanomolar, cell permeable inhibitors. Further elaboration revealed a channel that allowed access to the external Nluc surface, resulting in a series of highly potent cell impermeable Nluc inhibitors with negatively charged groups likely extending to the protein surface. The permeability was evaluated by comparing EC50 shifts calculated from both live and lysed cells expressing Nluc cytosolically. Luminescence imaging further confirmed that cell permeable compounds inhibit both intracellular and extracellular Nluc, whereas less permeable compounds differentially inhibit extracellular Nluc and Nluc on the cell surface. The compounds displayed little to no toxicity to cells and high luciferase specificity, showing no activity against firefly luciferase or even the closely related NanoBit system. Looking forward, the structural motifs used to gain access to the Nluc surface can also be appended with other functional groups, and therefore interesting opportunities for developing assays based on relief-of-inhibition can be envisioned.
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Affiliation(s)
- Joel R. Walker
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Mary P. Hall
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Chad A. Zimprich
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Matthew B. Robers
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Sarah J. Duellman
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Thomas Machleidt
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Jacquelynn Rodriguez
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
| | - Wenhui Zhou
- Promega Biosciences LLC, 277
Granada Drive, San Luis Obispo, California 93401, United States
- Promega Corporation, 2800 Woods
Hollow Road, Madison, Wisconsin 53711-5399, United States
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24
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Kilpatrick LE, Friedman-Ohana R, Alcobia DC, Riching K, Peach CJ, Wheal AJ, Briddon SJ, Robers MB, Zimmerman K, Machleidt T, Wood KV, Woolard J, Hill SJ. Real-time analysis of the binding of fluorescent VEGF 165a to VEGFR2 in living cells: Effect of receptor tyrosine kinase inhibitors and fate of internalized agonist-receptor complexes. Biochem Pharmacol 2017; 136:62-75. [PMID: 28392095 PMCID: PMC5457915 DOI: 10.1016/j.bcp.2017.04.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 04/04/2017] [Indexed: 01/01/2023]
Abstract
Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis. Here we have used a novel stoichiometric protein-labeling method to generate a fluorescent variant of VEGF (VEGF165a-TMR) labeled on a single cysteine within each protomer of the antiparallel VEGF homodimer. VEGF165a-TMR has then been used in conjunction with full length VEGFR2, tagged with the bioluminescent protein NanoLuc, to undertake a real time quantitative evaluation of VEGFR2 binding characteristics in living cells using bioluminescence resonance energy transfer (BRET). This provided quantitative information on VEGF-VEGFR2 interactions. At longer incubation times, VEGFR2 is internalized by VEGF165a-TMR into intracellular endosomes. This internalization can be prevented by the receptor tyrosine kinase inhibitors (RTKIs) cediranib, sorafenib, pazopanib or vandetanib. In the absence of RTKIs, the BRET signal is decreased over time as a consequence of the dissociation of agonist from the receptor in intracellular endosomes and recycling of VEGFR2 back to the plasma membrane.
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Affiliation(s)
- Laura E Kilpatrick
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | - Diana C Alcobia
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | - Chloe J Peach
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Amanda J Wheal
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Stephen J Briddon
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | | | | | | | - Jeanette Woolard
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom.
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom.
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25
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Somberg RL, Schwinn MK, Slater MR, Machleidt T, Cong M, Wood KV. Abstract 360: Detecting intracellular bRAF/cRAF dimerization using a novel luminescent complementation system. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
BRAF mutations can promote constitutive activation of MEK/ERK signaling, leading to unregulated cell proliferation and tumorigenesis. Although inhibitors targeting oncogenic BRAF have shown promise in preventing cell growth, these same inhibitors can paradoxically activate signaling by inducing BRAF interaction with CRAF. Methods for monitoring this undesired outcome are typically low throughput or use kinase binding domains modified with a membrane targeting sequence. We sought to develop a cell-based assay that could reliably detect dimerization of full-length BRAF/CRAF and could potentially be used to rapidly screen inhibitors for modulation of this interaction. To achieve this objective, we utilized a NanoLuc luciferase-based complementation reporter consisting of 1.3 kD (SmBiT) and 18 kD (LgBiT) fusion tags that reconstitute an active luciferase when brought into proximity. In this optimally configured BRAF/CRAF assay, BRAF-LgBiT and CRAF-SmBiT fusions are stably expressed in mammalian cells, and luminescence, indicative of protein interaction, is monitored using a live cell detection reagent. With this assay, we were able to observe rapid and dose-dependent induction of BRAF/CRAF dimerization in response to a panel of kinase inhibitors. The sensitivity and robustness of the assay permitted reliable screening in both 96- and 384-well formats (Z’ factors > 0.9 and 0.6, respectively). Furthermore, the brightness of the reporter allowed the assay to be monitored in individual cells using bioluminescence imaging. These results suggest this BRAF/CRAF complementation assay can enable rapid, high-throughput profiling of kinase inhibitors targeting the RAS/RAF/MEK/ERK signaling pathway.
Citation Format: Richard L. Somberg, Marie K. Schwinn, Michael R. Slater, Thomas Machleidt, Mei Cong, Keith V. Wood. Detecting intracellular bRAF/cRAF dimerization using a novel luminescent complementation system. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 360.
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26
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Kupcho K, Shultz J, Niles A, Zhou W, Hurst R, Hartnett J, Machleidt T, Riss T, Lazar D, Cali J. Abstract 3505: A bioluminescent, homogeneous annexin V microplate-based method for assessment of apoptosis. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-3505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The selective elimination of malignant cells via the apoptotic process continues to be the cornerstone of modern anti-cancer therapy regimens. Therefore, in vitro screening approaches aimed at identifying clinically useful apoptosis inducers remain critically important. Recently, phenotypic screening methods have enjoyed a resurgence due to more biologically complex and relevant cell models as well as advances in chemical proteomics which have allowed for more successful target identification. As a consequence, novel probes and tools with enabling attributes are required to fully realize this discovery potential. In an effort to address this unmet need, we have developed a bioluminescent and homogeneous annexin V binding assay for the assessment of apoptosis. Unlike traditional fluorescent annexin V methodology, the “no-wash” reagent employed in this new assay utilizes binary components of a novel luciferase separately fused to annexin V. The annexin V-luciferase subunit fusion pairs have low intrinsic affinity for each other and thus produce no or low luminescence until phosphatidylserine (PtdSer) exposure drives annexin-fusion pair oligimerization. Ultimately, this protein:protein interaction on or near the cell surface reconstitutes full luciferase activity causing an increase in luminescence in the presence of a luciferase substrate. A separate, pro-fluorescent, multiplexed component of the reagent further delineates differences in annexin positivity based on maintenance or loss of membrane integrity corresponding to apoptosis or necrosis, respectively. We validated this method using a panel of diverse cancer cell lines (U2-OS, DLD-1, HeLa, Jurkat, K562, A549, and PC-3), representing both attachment-dependent and -independent morphologies after dose-dependent challenge with intrinsic (bortezomib, panobinostat, staurosporine, and paclitaxel) and extrinsic (rhTRAIL) inducers of apoptosis as well as agents known to produce primary necrosis (ionomycin and digitonin). Caspase activation data was also collected in parallel plates at endpoint as a well-validated and sensitive orthogonal comparator. The bioluminescent annexin V method proved sufficiently robust in 384 well microplate formats to routinely produce Z’ > 0.7 and rank-order potencies in good agreement with caspase activation values. In addition to this microplate functionality, the reagent allowed for sensitive, facile imaging of apoptotic induction in living cells using different imaging platforms. Taken together, the method and reagent should provide unparalleled flexibility with regard to live cell apoptosis detection in both conventional microplate and high content-like imaging formats and advance the pace of new chemical entity discovery.
Citation Format: Kevin Kupcho, John Shultz, Andrew Niles, Wenhui Zhou, Robin Hurst, Jim Hartnett, Thomas Machleidt, Terry Riss, Dan Lazar, Jim Cali. A bioluminescent, homogeneous annexin V microplate-based method for assessment of apoptosis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3505.
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Affiliation(s)
| | | | | | - Wenhui Zhou
- 2Promega Biosciences LLC, San Luis Obispo, CA
| | | | | | | | | | | | - Jim Cali
- 1Promega Corporation, Madison, WI
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Shakhmin A, Hall MP, Walker JR, Machleidt T, Binkowski BF, Wood KV, Kirkland TA. Three Efficient Methods for Preparation of Coelenterazine Analogues. Chemistry 2016; 22:10369-75. [PMID: 27305599 DOI: 10.1002/chem.201601111] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 04/21/2016] [Indexed: 12/26/2022]
Abstract
The growing popularity of bioluminescent assays has highlighted the need for coelenterazine analogues possessing properties tuned for specific applications. However, the structural diversity of known coelenterazine analogues has been limited by current syntheses. Known routes for the preparation of coelenterazine analogues employ harsh reaction conditions that limit access to many substituents and functional groups. Novel synthetic routes reported here establish simple and robust methods for synthesis and investigation of structurally diverse marine luciferase substrates. Specifically, these new routes allow synthesis of coelenterazine analogues containing various heterocyclic motifs and substituted aromatic groups with diverse electronic substituents at the R(2) position. Interesting analogues described herein were characterized by their physicochemical properties, bioluminescent half-life, light output, polarity and cytotoxicity. Some of the analogues represent leads that can be utilized in the development of improved bioluminescent systems.
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Affiliation(s)
- Anton Shakhmin
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, CA, 93401, USA
| | - Mary P Hall
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711-5399, USA
| | - Joel R Walker
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, CA, 93401, USA
| | - Thomas Machleidt
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711-5399, USA
| | - Brock F Binkowski
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711-5399, USA
| | - Keith V Wood
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711-5399, USA
| | - Thomas A Kirkland
- Promega Biosciences LLC, 277 Granada Drive, San Luis Obispo, CA, 93401, USA.
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28
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Dixon AS, Schwinn MK, Hall MP, Zimmerman K, Otto P, Lubben TH, Butler BL, Binkowski BF, Machleidt T, Kirkland TA, Wood MG, Eggers CT, Encell LP, Wood KV. NanoLuc Complementation Reporter Optimized for Accurate Measurement of Protein Interactions in Cells. ACS Chem Biol 2016; 11:400-8. [PMID: 26569370 DOI: 10.1021/acschembio.5b00753] [Citation(s) in RCA: 738] [Impact Index Per Article: 92.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Protein-fragment complementation assays (PCAs) are widely used for investigating protein interactions. However, the fragments used are structurally compromised and have not been optimized nor thoroughly characterized for accurately assessing these interactions. We took advantage of the small size and bright luminescence of NanoLuc to engineer a new complementation reporter (NanoBiT). By design, the NanoBiT subunits (i.e., 1.3 kDa peptide, 18 kDa polypeptide) weakly associate so that their assembly into a luminescent complex is dictated by the interaction characteristics of the target proteins onto which they are appended. To ascertain their general suitability for measuring interaction affinities and kinetics, we determined that their intrinsic affinity (KD = 190 μM) and association constants (kon = 500 M(-1) s(-1), koff = 0.2 s(-1)) are outside of the ranges typical for protein interactions. The accuracy of NanoBiT was verified under defined biochemical conditions using the previously characterized interaction between SME-1 β-lactamase and a set of inhibitor binding proteins. In cells, NanoBiT fusions to FRB/FKBP produced luminescence consistent with the linear characteristics of NanoLuc. Response dynamics, evaluated using both protein kinase A and β-arrestin-2, were rapid, reversible, and robust to temperature (21-37 °C). Finally, NanoBiT provided a means to measure pharmacology of kinase inhibitors known to induce the interaction between BRAF and CRAF. Our results demonstrate that the intrinsic properties of NanoBiT allow accurate representation of protein interactions and that the reporter responds reliably and dynamically in cells.
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Affiliation(s)
- Andrew S. Dixon
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Mary P. Hall
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Kris Zimmerman
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Paul Otto
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | | | | | | | - Thomas A. Kirkland
- Promega Biosciences Incorporated, San Luis
Obispo, California 93401, United States
| | - Monika G. Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
| | | | - Lance P. Encell
- Promega Corporation, Madison, Wisconsin 53711, United States
| | - Keith V. Wood
- Promega Corporation, Madison, Wisconsin 53711, United States
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29
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Machleidt T, Woodroofe CC, Schwinn MK, Méndez J, Robers MB, Zimmerman K, Otto P, Daniels DL, Kirkland TA, Wood KV. NanoBRET--A Novel BRET Platform for the Analysis of Protein-Protein Interactions. ACS Chem Biol 2015; 10:1797-804. [PMID: 26006698 DOI: 10.1021/acschembio.5b00143] [Citation(s) in RCA: 311] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dynamic interactions between proteins comprise a key mechanism for temporal control of cellular function and thus hold promise for development of novel drug therapies. It remains technically challenging, however, to quantitatively characterize these interactions within the biologically relevant context of living cells. Although, bioluminescence resonance energy transfer (BRET) has often been used for this purpose, its general applicability has been hindered by limited sensitivity and dynamic range. We have addressed this by combining an extremely bright luciferase (Nanoluc) with a means for tagging intracellular proteins with a long-wavelength fluorophore (HaloTag). The small size (19 kDa), high emission intensity, and relatively narrow spectrum (460 nm peak intensity) make Nanoluc luciferase well suited as an energy donor. By selecting an efficient red-emitting fluorophore (635 nm peak intensity) for attachment onto the HaloTag, an overall spectral separation exceeding 175 nm was achieved. This combination of greater light intensity with improved spectral resolution results in substantially increased detection sensitivity and dynamic range over current BRET technologies. Enhanced performance is demonstrated using several established model systems, as well as the ability to image BRET in individual cells. The capabilities are further exhibited in a novel assay developed for analyzing the interactions of bromodomain proteins with chromatin in living cells.
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Affiliation(s)
- Thomas Machleidt
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Carolyn C. Woodroofe
- Promega Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, California 93401, United States
| | - Marie K. Schwinn
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Jacqui Méndez
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Matthew B. Robers
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Kris Zimmerman
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Paul Otto
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Danette L. Daniels
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
| | - Thomas A. Kirkland
- Promega Biosciences Incorporated, 277 Granada Drive, San Luis Obispo, California 93401, United States
| | - Keith V. Wood
- Promega Corporation, 2800 Woods
Hollow, Madison, Wisconsin 53711, United States
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30
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Robers MB, Binkowski BF, Cong M, Zimprich C, Corona C, McDougall M, Otto G, Eggers CT, Hartnett J, Machleidt T, Fan F, Wood KV. A luminescent assay for real-time measurements of receptor endocytosis in living cells. Anal Biochem 2015; 489:1-8. [PMID: 26278171 DOI: 10.1016/j.ab.2015.08.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/28/2015] [Accepted: 08/05/2015] [Indexed: 01/14/2023]
Abstract
Ligand-mediated endocytosis is a key autoregulatory mechanism governing the duration and intensity of signals emanating from cell surface receptors. Due to the mechanistic complexity of endocytosis and its emerging relevance in disease, simple methods capable of tracking this dynamic process in cells have become increasingly desirable. We have developed a bioluminescent reporter technology for real-time analysis of ligand-mediated receptor endocytosis using genetic fusions of NanoLuc luciferase with various G-protein-coupled receptors (GPCRs). This method is compatible with standard microplate formats, which should decrease work flows for high-throughput screens. This article also describes the application of this technology to endocytosis of epidermal growth factor receptor (EGFR), demonstrating potential applicability of the method beyond GPCRs.
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Affiliation(s)
| | | | - Mei Cong
- Promega Corporation, Fitchburg, WI 53711, USA
| | | | | | | | - George Otto
- Promega Corporation, Fitchburg, WI 53711, USA
| | | | | | | | - Frank Fan
- Promega Corporation, Fitchburg, WI 53711, USA
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31
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Robers MB, Dart M, Zimprich C, Kirkland T, Levin S, Machleidt T, Hartnett J, Zimmerman K, Ohana R, Daniels D, Cong M, Fan F, Wood K. Abstract 3512: Measuring intracellular target engagement and drug residence time with nanoBRET. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-3512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
We present a biophysical method to directly measure target engagement within intact mammalian cells using bioluminescence energy transfer (BRET). Compound interactions with intracellular targets can be detected with complete specificity by their ability to compete with energy transfer complexes introduced into the cells. These complexes can be detected at physiologically relevant levels by exploiting an extraordinarily bright luciferase (NanoLuc), together with fluorescent tracers optimized for cell-permeability and spectral resolution from the luciferase. We demonstrate applications of the technology for target engagement among key drug target classes, including; kinases, histone deacetylases (HDACs), bromodomains, and the methyltransferase EZH2. Intracellular selectivity and affinity profiles of various reference compounds and approved drugs will be presented. For a panel of HDAC inhibitors, affinity profiles for specific HDAC isozymes strongly correlate with phenotypic potencies (e.g. cell viability). Furthermore, the luminescent output of the energy transfer complex enables a technique to monitor ligand occupancy in real-time. Association and dissociation rates can be derived from the kinetic measurements, providing a means to quantify drug residence time on select targets within intact cell populations. This novel application of intracellular BRET should significantly advance target engagement work flows, and allow for intracellular target affinities to be coupled to phenotypic outcomes.
Citation Format: Matthew B. Robers, Melanie Dart, Chad Zimprich, Thomas Kirkland, Sergiy Levin, Thomas Machleidt, Jim Hartnett, Kris Zimmerman, Rachel Ohana, Danette Daniels, Mei Cong, Frank Fan, Keith Wood. Measuring intracellular target engagement and drug residence time with nanoBRET. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3512. doi:10.1158/1538-7445.AM2015-3512
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32
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Stoddart LA, Johnstone EKM, Wheal AJ, Goulding J, Robers MB, Machleidt T, Wood KV, Hill SJ, Pfleger KDG. Application of BRET to monitor ligand binding to GPCRs. Nat Methods 2015; 12:661-663. [PMID: 26030448 PMCID: PMC4488387 DOI: 10.1038/nmeth.3398] [Citation(s) in RCA: 178] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 04/04/2015] [Indexed: 01/17/2023]
Abstract
Bioluminescence resonance energy transfer (BRET) is a well-established method for investigating protein-protein interactions. Here we present a novel BRET approach to monitor ligand binding to G protein-coupled receptors (GPCRs) on the surface of living cells made possible by the use of fluorescent ligands in combination with a novel bioluminescent protein (NanoLuc) that can be readily expressed on the N-terminus of GPCRs.
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Affiliation(s)
- Leigh A Stoddart
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham Medical School, Nottingham, United Kingdom
| | - Elizabeth K M Johnstone
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, Australia
| | - Amanda J Wheal
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham Medical School, Nottingham, United Kingdom
| | - Joëlle Goulding
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham Medical School, Nottingham, United Kingdom
| | | | | | - Keith V Wood
- Promega Corporation, Madison, Wisconsin, United States
| | - Stephen J Hill
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham Medical School, Nottingham, United Kingdom.,Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, Australia
| | - Kevin D G Pfleger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,Centre for Medical Research, The University of Western Australia, Crawley, Western Australia, Australia
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33
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Robers MB, Machleidt T, Kirkland T, Woodroofe C, Fan F, Cong M, Wood K. Abstract 4272: NanoLucTM as an improved BRET donor to monitor EGFR interactions within living cells. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-4272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
As a small, versatile protein fusion reporter, NanoLuc™ luciferase offers superior brightness and sensitivity compared to any luciferase described to date. The small size and enhanced brightness of NanoLuc™ makes it ideally suited as an energy donor for Bioluminescence Resonance Energy Transfer (BRET) to a variety of fluorescent acceptors within living cells. By combining genetic reporters such as NanoLuc™ luciferase and HaloTag™ fluorescent labelling technology, it is possible to monitor the interactions of cell surface receptors such as EGFR with adapter proteins in response to growth factor stimulation. In addition to demonstrating inducible protein interactions, it may also be possible to apply this foundational BRET system to the measurement of ligand or small molecule binding events within living cells.
Citation Format: Matthew B. Robers, Thomas Machleidt, Thomas Kirkland, Carolyn Woodroofe, Frank Fan, Mei Cong, Keith Wood. NanoLucTM as an improved BRET donor to monitor EGFR interactions within living cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4272. doi:10.1158/1538-7445.AM2013-4272
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Hall MP, Unch J, Binkowski BF, Valley MP, Butler BL, Wood MG, Otto P, Zimmerman K, Vidugiris G, Machleidt T, Robers MB, Benink HA, Eggers CT, Slater MR, Meisenheimer PL, Klaubert DH, Fan F, Encell LP, Wood KV. Engineered luciferase reporter from a deep sea shrimp utilizing a novel imidazopyrazinone substrate. ACS Chem Biol 2012; 7:1848-57. [PMID: 22894855 PMCID: PMC3501149 DOI: 10.1021/cb3002478] [Citation(s) in RCA: 1032] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Bioluminescence methodologies have been extraordinarily
useful
due to their high sensitivity, broad dynamic range, and operational
simplicity. These capabilities have been realized largely through
incremental adaptations of native enzymes and substrates, originating
from luminous organisms of diverse evolutionary lineages. We engineered
both an enzyme and substrate in combination to create a novel bioluminescence
system capable of more efficient light emission with superior biochemical
and physical characteristics. Using a small luciferase subunit (19
kDa) from the deep sea shrimp Oplophorus gracilirostris, we have improved luminescence expression in mammalian cells ∼2.5
million-fold by merging optimization of protein structure with development
of a novel imidazopyrazinone substrate (furimazine). The new luciferase,
NanoLuc, produces glow-type luminescence (signal half-life >2 h)
with
a specific activity ∼150-fold greater than that of either firefly
(Photinus pyralis) or Renilla luciferases
similarly configured for glow-type assays. In mammalian cells, NanoLuc
shows no evidence of post-translational modifications or subcellular
partitioning. The enzyme exhibits high physical stability, retaining
activity with incubation up to 55 °C or in culture medium for
>15 h at 37 °C. As a genetic reporter, NanoLuc may be configured
for high sensitivity or for response dynamics by appending a degradation
sequence to reduce intracellular accumulation. Appending a signal
sequence allows NanoLuc to be exported to the culture medium, where
reporter expression can be measured without cell lysis. Fusion onto
other proteins allows luminescent assays of their metabolism or localization
within cells. Reporter quantitation is achievable even at very low
expression levels to facilitate more reliable coupling with endogenous
cellular processes.
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Affiliation(s)
- Mary P. Hall
- Promega Corporation, Madison, Wisconsin
53711 United States
| | - James Unch
- Promega Biosciences Incorporated, San Luis Obispo, California 93401 United
States
| | | | | | | | - Monika G. Wood
- Promega Corporation, Madison, Wisconsin
53711 United States
| | - Paul Otto
- Promega Corporation, Madison, Wisconsin
53711 United States
| | | | | | | | | | | | | | | | | | - Dieter H. Klaubert
- Promega Biosciences Incorporated, San Luis Obispo, California 93401 United
States
| | - Frank Fan
- Promega Corporation, Madison, Wisconsin
53711 United States
| | | | - Keith V. Wood
- Promega Corporation, Madison, Wisconsin
53711 United States
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Kopish K, Hall M, Binkowski B, Valley M, Butler B, Machleidt T, Robers M, Eggers C, Encell L, Wood K. 188 NanoLuc: a Smaller, Brighter, and More Versatile Luciferase Reporter. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71986-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Zhang T, Inesta-Vaquera F, Niepel M, Zhang J, Ficarro SB, Machleidt T, Xie T, Marto JA, Kim N, Sim T, Laughlin JD, Park H, LoGrasso PV, Patricelli M, Nomanbhoy TK, Sorger PK, Alessi DR, Gray NS. Discovery of potent and selective covalent inhibitors of JNK. ACTA ACUST UNITED AC 2012; 19:140-54. [PMID: 22284361 DOI: 10.1016/j.chembiol.2011.11.010] [Citation(s) in RCA: 247] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 11/11/2011] [Accepted: 11/17/2011] [Indexed: 12/11/2022]
Abstract
The mitogen-activated kinases JNK1/2/3 are key enzymes in signaling modules that transduce and integrate extracellular stimuli into coordinated cellular response. Here, we report the discovery of irreversible inhibitors of JNK1/2/3. We describe two JNK3 cocrystal structures at 2.60 and 2.97 Å resolution that show the compounds form covalent bonds with a conserved cysteine residue. JNK-IN-8 is a selective JNK inhibitor that inhibits phosphorylation of c-Jun, a direct substrate of JNK, in cells exposed to submicromolar drug in a manner that depends on covalent modification of the conserved cysteine residue. Extensive biochemical, cellular, and pathway-based profiling establish the selectivity of JNK-IN-8 for JNK and suggests that the compound will be broadly useful as a pharmacological probe of JNK-dependent signal transduction. Potential lead compounds have also been identified for kinases, including IRAK1, PIK3C3, PIP4K2C, and PIP5K3.
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Affiliation(s)
- Tinghu Zhang
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
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Machleidt T, Robers MB, Hermanson SB, Dudek JM, Bi K. TR-FRET cellular assays for interrogating posttranslational modifications of histone H3. ACTA ACUST UNITED AC 2011; 16:1236-46. [PMID: 21972037 DOI: 10.1177/1087057111422943] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Posttranslational modifications such as phosphorylation, acetylation, and methylation play important roles in regulating the structures and functions of histones, which in turn regulate gene expression and DNA repair and replication. Histone-modifying enzymes, such as deacetylases, methyltransferases and demethylases, have been pursued as therapeutic targets for various diseases. However, detection of the activities of these enzymes in high-throughput cell-based formats has remained challenging. The authors have developed high-throughput LanthaScreen cellular assays for Histone H3 site-specific modifications. These assays use cells expressing green fluorescence protein-tagged Histone H3 transiently delivered via BacMam and terbium-labeled anti-Histone H3 modification-specific antibodies. Robust time-resolved Förster resonance energy transfer signals were detected for H3 lysine-9 acetylation and dimethylation (H3K9me2), serine-10 phosphorylation, K4 di- and trimethylation, and K27 trimethylation. Consistent with previous reports, hypoxic stress increased K4 methylation levels, and methyltransferase G9a inhibitor UNC-0638 decreased K9me2 levels significantly, with little effects on other modifications. To demonstrate the utility of this assay platform in screening, the K9 acetylation assay was used to profile the Enzo Epigenetics Library. Twelve known HDAC inhibitors were identified as hits and followed up in a dose-response format. In conclusion, this assay platform enables high-throughput cell-based analysis of diverse types of posttranslational modifications of Histone H3.
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Affiliation(s)
- Thomas Machleidt
- Life Technologies Corporation, Discovery and ADMET Systems, Madison, WI 53719, USA
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38
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Stebbins JL, De SK, Pavlickova P, Chen V, Machleidt T, Chen LH, Kuntzen C, Kitada S, Karin M, Pellecchia M. Design and characterization of a potent and selective dual ATP- and substrate-competitive subnanomolar bidentate c-Jun N-terminal kinase (JNK) inhibitor. J Med Chem 2011; 54:6206-14. [PMID: 21815634 DOI: 10.1021/jm200479c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
c-Jun N-terminal kinases (JNKs) represent valuable targets in the development of new therapies. Present on the surface of JNK is a binding pocket for substrates and the scaffolding protein JIP1 in close proximity to the ATP binding pocket. We propose that bidentate compounds linking the binding energies of weakly interacting ATP and substrate mimetics could result in potent and selective JNK inhibitors. We describe here a bidentate molecule, 19, designed against JNK. 19 inhibits JNK kinase activity (IC(50) = 18 nM; K(i) = 1.5 nM) and JNK/substrate association in a displacement assay (IC(50) = 46 nM; K(i) = 2 nM). Our data demonstrate that 19 targets for the ATP and substrate-binding sites on JNK concurrently. Finally, compound 19 successfully inhibits JNK in a variety of cell-based experiments, as well as in vivo where it is shown to protect against Jo-2 induced liver damage and improve glucose tolerance in diabetic mice.
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Affiliation(s)
- John L Stebbins
- Infectious and Inflammatory Disease Center, Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
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Hallis T, Bi K, Machleidt T, Hermanson S, Wilkinson J, Wetter J. Abstract 67: High-throughput cellular assays for interrogating epigenetic histone modifications. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-67] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Epigenetic histone modifications such as, methylation, acetylation, and phosphorylation play important roles in regulating the structure and functions of histones which in turn regulate essential gene expression. Dysregulation of the enzymes responsible for these modifications has been linked to cancer and many other diseases. In particular, histone deacetylases (HDACs) and histone methyl transferase (HMTs) have been a recent focus for drug discovery. However, detection of these enzymatic activities in an HTS cell-based format has remained challenging, especially since many of these enzymes may require the formation of protein complexes for relevant activity. To help overcome these challenges, we have developed and validated high-throughput compatible LanthaScreen® cellular assays for the analysis of histone methylation, acetylation, and phoshorylation, in cell backgrounds of interest. The acetylation, methylation and phosphorylation of H3 at specific residues can be detected with terbium-labeled antibodies against the specific site and modification. The expression of GFP-H3 substrate allows for detection of antibody binding in cell lysates via TR-FRET between the terbium and GFP. Since the actual modification takes place in the intact cell, native protein complexes that may be important for enzyme function are preserved. Together, these assays enable interrogation of multiple enzymatic activities responsible for epigenetic modifications of challenging histone targets
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 67. doi:10.1158/1538-7445.AM2011-67
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Affiliation(s)
| | - Kun Bi
- 1Life Technologies Corp, Madison, WI
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40
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De SK, Barile E, Chen V, Stebbins JL, Cellitti JF, Machleidt T, Carlson CB, Yang L, Dahl R, Pellecchia M. Design, synthesis, and structure-activity relationship studies of thiophene-3-carboxamide derivatives as dual inhibitors of the c-Jun N-terminal kinase. Bioorg Med Chem 2011; 19:2582-8. [PMID: 21458276 DOI: 10.1016/j.bmc.2011.03.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 03/01/2011] [Accepted: 03/07/2011] [Indexed: 01/07/2023]
Abstract
We report comprehensive structure-activity relationship studies on a novel series of c-Jun N-terminal kinase (JNK) inhibitors. Intriguingly, the compounds have a dual inhibitory activity by functioning as both ATP and JIP mimetics, possibly by binding to both the ATP binding site and to the docking site of the kinase. Several of such novel compounds display potent JNK inhibitory profiles both in vitro and in cell.
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Affiliation(s)
- Surya K De
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA
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41
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Robers M, Machleidt T, Hermanson S, Wilkinson J, Wetter J, Bi K. Abstract 4867: High-throughput LanthaScreen® cellular assays for interrogating post-translational modifications of p53 and histones. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-4867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Post-translational modifications such as phosphorylation, acetylation and ubquitination play important roles in regulating the structure and functions of histones and transcription factors such as p53, which in turn regulate essential gene expression. Dysregulation of these post-translational modifications has been linked to cancer and metabolic diseases. In particular, histone deacetylases (HDACs) have been pursued as valuable targets for various therapeutic interventions. However, detection of these enzymatic activities in a cell-based format has remained intractable using HTS-compatible technologies. To enable the drug discovery for these post-translational modification enzymes, we have developed and validated high-throughput compatible LanthaScreen® cellular assays for the analysis of histone and/or p53-specific acetylation, ubquitination and phoshorylation in cell backgrounds of interest. The cell cycle-dependent acetylation of histone H3 at Lys9 and the phosphorylation of histone H3 at Ser10 can be detected with terbium-labeled anti-Histone H3 acetyl-lys 9 and anti-phospho-Ser10 specific antibodies, respectively. In addition, poly-ubiquitination of Histone H2B can be measured with terbium-labeled anti-poly-ubiquitin antibody. We have also applied this technology and developed cellular assays for measuring DNA-damage induced phosphorylation at Ser15 and acetylation at Lys382 of p53. These assays were further validated with both small molecule inhibitor and siRNA against specific HDAC family members. Our results suggest that the deacetylation of Histone H3 Lys 9 is mediated by type I/II HDACs, whereas the deacetylation of p53 at Lys382 is mediated synergistically by both SIRT1 and type I/II HDAC activities. Together, these assays enable interrogation of multiple enzymatic activities responsible for post-translational modifications of challenging targets such as histones and p53.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4867.
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Affiliation(s)
- Matt Robers
- 1Invitrogen, Part of Life Technologies, Madison, WI
| | | | | | | | | | - Kun Bi
- 1Invitrogen, Part of Life Technologies, Madison, WI
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De SK, Chen V, Stebbins JL, Chen LH, Cellitti JF, Machleidt T, Barile E, Riel-Mehan M, Dahl R, Yang L, Emdadi A, Murphy R, Pellecchia M. Synthesis and optimization of thiadiazole derivatives as a novel class of substrate competitive c-Jun N-terminal kinase inhibitors. Bioorg Med Chem 2009; 18:590-6. [PMID: 20045647 DOI: 10.1016/j.bmc.2009.12.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 11/30/2009] [Accepted: 12/03/2009] [Indexed: 11/24/2022]
Abstract
A series of thiadiazole derivatives has been designed as potential allosteric, substrate competitive inhibitors of the protein kinase JNK. We report on the synthesis, characterization and evaluation of a series of compounds that resulted in the identification of potent and selective JNK inhibitors targeting its JIP-1 docking site.
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Affiliation(s)
- Surya K De
- Burnham Institute for Medical Research, La Jolla, CA 92037, USA
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Lieu PT, Machleidt T, Thyagarajan B, Fontes A, Frey E, Fuerstenau-Sharp M, Thompson DV, Swamilingiah GM, Derebail SS, Piper D, Chesnut JD. Generation of Site-Specific Retargeting Platform Cell Lines for Drug Discovery Using phiC31 and R4 Integrases. ACTA ACUST UNITED AC 2009; 14:1207-15. [DOI: 10.1177/1087057109348941] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
One of the challenges in developing cell lines for high-throughput screening in drug discovery is the labor- and time-intensive process required to create stable clonal cell lines that express specific reporters or drug targets. The authors report here the generation of a site-specific retargeting platform in 3 different cell lines: adherent HEK293, suspension CHO-S, and a human embryonic cell line (BGO1V). These platform cell lines were generated by using a combination of 2 site-specific integrases to develop a system that allows one to efficiently target a gene of interest to a specific locus and generates rapid production of homogeneous cell pools that stably express the gene of interest. The phiC31 integrase was used to create a platform line by placing a target site for the R4 integrase into a pseudo attP site, and then the R4 integrase was used to place a gene of interest into specific R4 target site. The authors demonstrate the successful and rapid retargeting of a G-protein-coupled receptor (cholecystokinin receptor A, CCKAR), an ion channel (the transient receptor potential cation channel, subfamily M, member 8, TRPM8), and a GFP-c-Jun(1-79) fusion protein into the specific loci in these cell lines and show that these retargeted cell lines exhibit functional and pharmacological responses consistent with those reported in the literature.
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Huwiler KG, Machleidt T, Chase L, Hanson B, Robers MB. Characterization of serotonin 5-hydroxytryptamine-1A receptor activation using a phospho-extracellular-signal regulated kinase 2 sensor. Anal Biochem 2009; 393:95-104. [DOI: 10.1016/j.ab.2009.06.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2009] [Accepted: 06/15/2009] [Indexed: 11/16/2022]
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45
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Robers M, Pinson P, Leong L, Batchelor RH, Gee KR, Machleidt T. Fluorescent labeling of proteins in living cells using the FKBP12 (F36V) tag. Cytometry A 2009; 75:207-24. [PMID: 18837033 DOI: 10.1002/cyto.a.20649] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Over the past decade live cell imaging has become a key technology to monitor and understand the dynamic behavior of proteins in the physiological context of living cells. The visualization of a protein of interest is most commonly achieved by genetically fusing it to green fluorescent protein (GFP) or one of it variants. Considerable effort has been made to develop alternative methods of protein labeling to overcome the intrinsic limitations of fluorescent proteins. In this report we show the optimization of a live cell labeling technology based on the use of a mutant form of FKBP12 (FKBP12(F36V)) in combination with a synthetic high affinity ligand (SLF') that specifically binds to this mutant. It had been previously shown that the use of a fluorescein-conjugated form of SLF' (5'-fluorescein-SLF') allowed the labeling of proteins genetically fused to FKBP-F36V in living cells. Here we describe the identification of novel fluorescent SLF'dye conjugates that allow specific labeling of FKBP12(F36V) fusion proteins in living cells. To further increase the versatility of this technology we developed a number of technical improvements. We implemented the use of pluronics during the labeling process to facilitate the uptake of the SLF'-dye conjugates and the use suppression dyes to reduce background signal. Furthermore, the time and dose dependency of labeling was investigated in order to determine optimal labeling conditions. Finally, the specificity of the FKBP12(F36V) labeling technology was extensively validated by morphological analysis using a diverse set of FKBP12(F36V) fusions proteins. In addition we show a number of different application examples, such as translocation assays, the generation of biosensors, and multiplex labeling in combination with different labeling technologies, such as FlAsH or GFP. In summary we show that the FKBP12(F36V)/SLF' labeling technology has a broad range of applications and should prove useful for the study of protein function in living cells.
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Affiliation(s)
- Matt Robers
- Invitrogen Discovery Sciences, Madison, Wisconsin 53719, USA
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Machleidt T, Whitney P, Bi K. Multiplexing of pathway-specific beta-lactamase reporter gene assays by optical coding with Qtracker nanocrystals. ACTA ACUST UNITED AC 2009; 14:845-52. [PMID: 19502565 DOI: 10.1177/1087057109335742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Reporter assays are widely used in research and drug discovery for analysis of signaling pathways in a cell-based format. Traditionally, reporter gene assays are run in a single-parameter mode, interrogating only 1 pathway per sample. To enable more complex assay formats for pathway analysis, the authors developed a multiplexed reporter cell-based assay that combines optical encoding with a beta-lactamase reporter gene readout. The optical encoding is achieved by peptide-mediated delivery of quantum dots into reporter cell lines. Using different quantum dots, the authors were able to simultaneously analyze multiple signaling pathways in the same sample using fluorescence microscopy or flow cytometry. They selected 3 beta-lactamase reporter cell lines for the analysis of tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), and interferon gamma (IFN-gamma) induced signaling to perform proof-of-principle experiments. The analysis demonstrates that this multiplexed assay allows the reliable detection of ligand-specific activation patterns as well as pathway-specific inhibitors. This method provides a template for the development of novel assay designs that enable the analysis of complex signaling networks involving multiple signaling pathways as well as cell-specific pathways in heterotypic cell models.
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Affiliation(s)
- Thomas Machleidt
- Invitrogen Discovery Assays and Services, Madison, Wisconsin 53719, USA.
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De SK, Stebbins JL, Chen LH, Riel-Mehan M, Machleidt T, Dahl R, Yuan H, Emdadi A, Barile E, Chen V, Murphy R, Pellecchia M. Design, synthesis, and structure-activity relationship of substrate competitive, selective, and in vivo active triazole and thiadiazole inhibitors of the c-Jun N-terminal kinase. J Med Chem 2009; 52:1943-52. [PMID: 19271755 DOI: 10.1021/jm801503n] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report comprehensive structure-activity relationship studies on a novel series of c-Jun N-terminal kinase (JNK) inhibitors. The compounds are substrate competitive inhibitors that bind to the docking site of the kinase. The reported medicinal chemistry and structure-based optimizations studies resulted in the discovery of selective and potent thiadiazole JNK inhibitors that display promising in vivo activity in mouse models of insulin insensitivity.
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Affiliation(s)
- Surya K De
- Infectious and Inflammatory Disease Center and Cancer Center, Burnham Institute for Medical Research, La Jolla, California 92037, USA
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De SK, Chen LH, Stebbins JL, Machleidt T, Riel-Mehan M, Dahl R, Chen V, Yuan H, Barile E, Emdadi A, Murphy R, Pellecchia M. Discovery of 2-(5-nitrothiazol-2-ylthio)benzo[d]thiazoles as novel c-Jun N-terminal kinase inhibitors. Bioorg Med Chem 2009; 17:2712-7. [PMID: 19282190 DOI: 10.1016/j.bmc.2009.02.046] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 02/17/2009] [Accepted: 02/20/2009] [Indexed: 11/17/2022]
Abstract
A new series of 2-thioether-benzothiazoles has been synthesized and evaluated for JNK inhibition. The SAR studies led to the discovery of potent, allosteric JNK inhibitors with selectivity against p38.
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Affiliation(s)
- Surya K De
- Burnham Institute for Medical Research, La Jolla, CA 92037, USA
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Carlson CB, Robers MB, Vogel KW, Machleidt T. Development of LanthaScreen cellular assays for key components within the PI3K/AKT/mTOR pathway. ACTA ACUST UNITED AC 2009; 14:121-32. [PMID: 19196698 DOI: 10.1177/1087057108328132] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The PI3K/AKT/mTOR pathway is central to cell growth and survival, cell cycle regulation, and programmed cell death. Aberrant activation of this signaling cascade is linked to several disease states, and thus many components of the pathway are attractive targets for therapeutic intervention. However, the considerable degree of complexity, crosstalk, and feedback regulation that exists within the pathway (especially with respect to the regulation of mTOR and its complexes) underscores the need for a comprehensive set of cell-based assays to properly identify and characterize small-molecule modulators. Here, the development and application of time-resolved Förster resonance energy transfer (TR-FRET)-based assays to enable the phosphoprotein analysis of key pathway components in a cellular format are reported. The LanthaScreen cellular assay platform uses FRET between a terbium-labeled phosphorylation site-specific antibody and an expressed green fluorescent protein fusion of particular kinase substrate and provides an assay readout that is ratiometric, robust, and amenable to high-throughput screening applications. Assays specific for 5 different targets within the pathway are highlighted: Ser183 and Thr246 on the proline-rich AKT substrate 40 kDa (PRAS40), Ser457 on programmed cell death protein 4 (PDCD4), and Thr308 and Ser473 on AKT. Each assay was evaluated under various experimental conditions and individually optimized for performance. Known pathway agonists and a small panel of commercially available compounds were also used to complete the assay validation. Taken together, these data demonstrate the utility of a related set of cell-based assays to interrogate PI3K/AKT/mTOR signaling and provide a template for the development of similar assays for other targets.
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Affiliation(s)
- Coby B Carlson
- Invitrogen Discovery Sciences, Madison, Wisconsin 53719, USA.
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Robers MB, Machleidt T, Carlson CB, Bi K. Cellular LanthaScreen and beta-lactamase reporter assays for high-throughput screening of JAK2 inhibitors. Assay Drug Dev Technol 2008; 6:519-29. [PMID: 18694336 DOI: 10.1089/adt.2008.144] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 5 pathway is responsible for regulation of cellular responses to a number of cytokines and growth factors. In hematopoietic cells, growth factors such as granulocyte macrophage-colony stimulating factor, interleukin-3, and erythropoietin induce the activation of JAK2, which leads to the phosphorylation, dimerization, and transactivation of STAT5 proteins. Dysregulation of JAK2 by activating mutations such as JAK2V617F results in constitutive phosphorylation of STAT5 and has been linked to numerous myeloproliferative disorders such as polycythemia vera. A cellular LanthaScreen (Invitrogen Corp., Carlsbad, CA) time-resolved Förster resonance energy transfer assay for wild-type JAK2 activity was developed. This assay utilized the growth factor-dependent human erythroleukemia TF1 cell line engineered to express a green fluorescent protein-STAT5 fusion protein. Furthermore, a complementary beta-lactamase reporter gene assay was developed to analyze the transcriptional activity of STAT5 downstream of JAK2 in TF1 cells. The same technologies were applied to the development of cellular assays for the interrogation of the disease-relevant JAK2V617F activating mutant. A small molecule inhibitor and Stealth (Invitrogen Corp.) RNA interference oligonucleotides were used to confirm the involvement of JAK2. Our results suggest that these cellular assays and validation tools represent powerful integrated methods for the analysis of physiological and disease-relevant JAK/STAT pathways within the physiological cellular context.
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Affiliation(s)
- Matthew B Robers
- Invitrogen Corporation, 501 Charmany Drive, Madison, WI 53719, USA
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