scholarly journals Cardiac RyR N-terminal region biosensors for FRET-based high-throughput screening

2021 ◽  
Author(s):  
Jingyan Zhang ◽  
Siobhan M. Wong King Yuen ◽  
Jacob A. Schwarz ◽  
Levy M. Treinen ◽  
Ching-Chieh Tung ◽  
...  
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Large Scale ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Terminal Region ◽  
Excitation Contraction Coupling ◽  
Contraction Coupling ◽  
Donor And Acceptor ◽  
Small Molecule Modulators

AbstractThe N-terminal region (NTR) of the ryanodine receptor (RyR) calcium channels is critical to the regulation of Ca2+ release during excitation-contraction coupling. NTR hosts numerous mutations linked to skeletal and cardiac myopathies (RyR1 and RyR2, respectively), highlighting its potential as therapeutic target. Here, we labeled the NTR of mouse RyR2 at subdomains A, B, and C with donor and acceptor pairs for fluorescence resonance energy transfer (FRET), obtaining two biosensors. Using fluorescence lifetime (FLT)-detection of intramolecular FRET, we developed high-throughput screening (HTS) assays with the biosensors to identify small-molecule modulators of RyR. We screened a 1280-compound validation library and identified several hits. Hits with saturable FRET dose-response profiles, and previously unreported effects on RyR activity, were further tested using [3H]ryanodine binding to isolated sarcoplasmic reticulum vesicles, to measure their effects on full-length RyR opening in its natural membrane environment. We identified three novel inhibitors of both RyR1 and RyR2, and two RyR1-selective inhibitors at nanomolar Ca2+. These compounds may function as inhibitors of leaky RyRs in muscle. Two of these hits activated RyR1 only at micromolar Ca2+, highlighting them as potential activators of excitation-contraction coupling. These results indicate that large-scale HTS using this platform can lead to compounds with potential for therapeutic development.

scholarly journals Repurposing a Histamine Detection Platform for High-Throughput Screening of Histidine Decarboxylase

2018 ◽  
Vol 23 (9) ◽  
pp. 974-981
Author(s):  
Yu-Chi Juang ◽  
Xavier Fradera ◽  
Yongxin Han ◽  
Anthony William Partridge
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Large Scale ◽  
Histidine Decarboxylase ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Gastric Ulcers ◽  
Statistical Parameters ◽  
Time Resolved ◽  
Neurological Response

Histidine decarboxylase (HDC) is the primary enzyme that catalyzes the conversion of histidine to histamine. HDC contributes to many physiological responses as histamine plays important roles in allergic reaction, neurological response, gastric acid secretion, and cell proliferation and differentiation. Small-molecule modulation of HDC represents a potential therapeutic strategy for a range of histamine-associated diseases, including inflammatory disease, neurological disorders, gastric ulcers, and select cancers. High-throughput screening (HTS) methods for measuring HDC activity are currently limited. Here, we report the development of a time-resolved fluorescence resonance energy transfer (TR-FRET) assay for monitoring HDC activity. The assay is based on competition between HDC-generated histamine and fluorophore-labeled histamine for binding to a Europium cryptate (EuK)-labeled anti-histamine antibody. We demonstrated that the assay is highly sensitive and simple to develop. Assay validation experiments were performed using low-volume 384-well plates and resulted in good statistical parameters. A pilot HTS screen gave a Z′ score > 0.5 and a hit rate of 1.1%, and led to the identification of a validated hit series. Overall, the presented assay should facilitate the discovery of therapeutic HDC inhibitors by acting as a novel tool suitable for large-scale HTS and subsequent interrogation of compound structure–activity relationships.

scholarly journals Live-Cell Cardiac-Specific High-Throughput Screening Platform for Drug-Like Molecules That Enhance Ca2+ Transport

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1170 ◽  
Author(s):  
Tory M. Schaaf ◽  
Evan Kleinboehl ◽  
Samantha L. Yuen ◽  
Lauren N. Roelike ◽  
Bengt Svensson ◽  
...  
Keyword(s):  
Heart Failure ◽  
High Throughput ◽  
High Throughput Screening ◽  
High Speed ◽  
Large Scale ◽  
Transmembrane Protein ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Inhibitory Interaction ◽  
Single Polypeptide Chain

We engineered a concatenated fluorescent biosensor and dual-wavelength fluorescence lifetime (FLT) detection, to perform high-throughput screening (HTS) in living cells for discovery of potential heart-failure drugs. Heart failure is correlated with insufficient activity of the sarcoplasmic reticulum Ca-pump (SERCA2a), often due to excessive inhibition by phospholamban (PLB), a small transmembrane protein. We sought to discover small molecules that restore SERCA2a activity by disrupting this inhibitory interaction between PLB and SERCA2a. Our approach was to fluorescently tag the two proteins and measure fluorescence resonance energy transfer (FRET) to detect changes in binding or structure of the complex. To optimize sensitivity to these changes, we engineered a biosensor that concatenates the two fluorescently labeled proteins on a single polypeptide chain. This SERCA2a-PLB FRET biosensor construct is functionally active and effective for HTS. By implementing 2-wavelength FLT detection at extremely high speed during primary HTS, we culled fluorescent compounds as false-positive Hits. In pilot screens, we identified Hits that alter the SERCA2a-PLB interaction, and a newly developed secondary calcium uptake assay revealed both activators and inhibitors of Ca-transport. We are implementing this approach for large-scale screens to discover new drug-like modulators of SERCA2a-PLB interactions for heart failure therapeutic development.

scholarly journals A High-Throughput Continuous Assay for Screening and Characterization of Inhibitors of HIV Reverse-Transcriptase DNA Polymerase Activity

2011 ◽  
Vol 16 (5) ◽  
pp. 518-524 ◽  
Author(s):  
Elizabeth Cauchon ◽  
Jean-Pierre Falgueyret ◽  
Anick Auger ◽  
Roman A. Melnyk
Keyword(s):  
Reverse Transcriptase ◽  
High Throughput ◽  
High Throughput Screening ◽  
Antiviral Agents ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Polymerase Activity ◽  
Hiv Reverse Transcriptase ◽  
Donor And Acceptor

The authors have devised a continuous fluorescence-based assay to measure HIV reverse transcriptase (RT) polymerase activity for both high-throughput screening (HTS) and mechanistic characterization of inhibitors. The designed substrate is composed of a recessed DNA primer annealed to a DNA template that is labeled at the 5′-terminus with a donor fluorophore (AlexaFluor 488). RT-catalyzed incorporation of an acceptor-labeled deoxyuridine (dUTP-AlexaFluor 555) at the 3′-terminus of the fully extended DNA primer juxtaposes donor and acceptor fluorophores, resulting in robust fluorescence resonance energy transfer that can be monitored kinetically in real time. The assay is sensitive, permitting the use of low enzyme concentrations (<0.5 nM), and can be miniaturized for use in 384-well HTS mode. The authors further show that this assay is capable of evaluating inhibitor mechanism of action by confirming the binding mechanism of a set of nonnucleoside RT inhibitors. Given the versatility and the lack of requirement for costly platforms or radioactivity, this assay may serve to accelerate and streamline the discovery and characterization process for future antiviral agents.

scholarly journals TR-FRET-Based High-Throughput Screening Assay for Identification of UBC13 Inhibitors

2011 ◽  
Vol 17 (2) ◽  
pp. 163-176 ◽  
Author(s):  
Charitha Madiraju ◽  
Kate Welsh ◽  
Michael P. Cuddy ◽  
Paulo H. Godoi ◽  
Ian Pass ◽  
...  
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Large Scale ◽  
Inflammatory Diseases ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Chemical Library ◽  
Screening Assay ◽  
Time Resolved ◽  
High Throughput Screening Assay

UBC13 is a noncanonical ubiquitin conjugating enzyme (E2) that has been implicated in a variety of cellular signaling processes due to its ability to catalyze formation of lysine 63–linked polyubiquitin chains on various substrates. In particular, UBC13 is required for signaling by a variety of receptors important in immune regulation, making it a candidate target for inflammatory diseases. UBC13 is also critical for double-strand DNA repair and thus a potential radiosensitizer and chemosensitizer target for oncology. The authors developed a high-throughput screening (HTS) assay for UBC13 based on the method of time-resolved fluorescence resonance energy transfer (TR-FRET). The TR-FRET assay combines fluorochrome (Fl)–conjugated ubiquitin (fluorescence acceptor) with terbium (Tb)–conjugated ubiquitin (fluorescence donor), such that the assembly of mixed chains of Fl- and Tb-ubiquitin creates a robust TR-FRET signal. The authors defined conditions for optimized performance of the TR-FRET assay in both 384- and 1536-well formats. Chemical library screens (total 456 865 compounds) were conducted in high-throughput mode using various compound collections, affording superb Z′ scores (typically >0.7) and thus validating the performance of the assays. Altogether, the HTS assays described here are suitable for large-scale, automated screening of chemical libraries in search of compounds with inhibitory activity against UBC13.

scholarly journals A SARS-CoV-2 nucleocapsid protein TR-FRET assay amenable to high-throughput screening

2021 ◽  
Author(s):  
Kirill Gorshkov ◽  
Desarey Morales Vasquez ◽  
Kevin Chiem ◽  
Chengjin Ye ◽  
Bruce Nguyen Tran ◽  
...  
Keyword(s):  
Drug Development ◽  
High Throughput ◽  
Nucleocapsid Protein ◽  
High Throughput Screening ◽  
Antiviral Agents ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Drug Repurposing ◽  
Drug Efficacy ◽  
Donor And Acceptor

Drug development for specific antiviral agents against coronavirus disease 2019 (COVID-19) is still an unmet medical need as the pandemic continues to spread globally. Although huge efforts for drug repurposing and compound screens have put forth, only few compounds remain in late stage clinical trials. New approaches and assays are needed to accelerate COVID-19 drug discovery and development. Here we report a time-resolved fluorescence resonance energy transfer-based assay that detects the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (NP) produced in infected cells. It uses two specific anti-NP monoclonal antibodies (MAbs) conjugated to donor and acceptor fluorophores that produces a robust ratiometric signal for high throughput screening of large compound collections. Using this assay, we measured a half maximal inhibitory concentration (IC50) for Remdesivir of 9.3 μM against infection with SARS-CoV-2 USA/WA1/2020 (WA-1). The assay also detected SARS-CoV-2 South African (Beta, β), Brazilian/Japanese variant P.1 (Gamma, γ), and Californian (Epsilon, ε), variants of concern or interest (VoC). Therefore, this homogeneous SARS-CoV-2 NP detection assay can be used for accelerating lead compound discovery for drug development and for evaluating drug efficacy against emerging SARS-CoV-2 VoC.

High-throughput screening of TRPV1 ligands in the light of the Bioluminescence Resonance Energy Transfer technique

2021 ◽  
pp. MOLPHARM-AR-2021-000271
Author(s):  
Yann Chappe ◽  
Pauline Michel ◽  
Alexandre Joushomme ◽  
Solène Barbeau ◽  
Sandra Pierredon ◽  
...  
Keyword(s):  
Energy Transfer ◽  
High Throughput ◽  
High Throughput Screening ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Bioluminescence Resonance Energy Transfer

scholarly journals Assay Concordance between SPA and TR-FRET in High-Throughput Screening

2006 ◽  
Vol 11 (6) ◽  
pp. 606-616 ◽  
Author(s):  
Oliver Von Ahsen ◽  
Anne Schmidt ◽  
Monika Klotz ◽  
Karsten Parczyk
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Statistical Significance ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Time Resolved ◽  
Detection Technology ◽  
Significant Difference ◽  
Set Up ◽  
Detection Technologies

High-throughput screening (HTS) of large chemical libraries has become the main source of new lead compounds for drug development. Several specialized detection technologies have been developed to facilitate the cost- and time-efficient screening of millions of compounds. However, concerns have been raised, claiming that different HTS technologies may produce different hits, thus limiting trust in the reliability of HTS data. This study was aimed to investigate the reliability of the authors most frequently used assay techniques: scintillation proximity assay (SPA) and homogeneous time-resolved fluorescence resonance energy transfer (TR-FRET). To investigate the data concordance between these 2 detection technologies, the authors screened a large subset of the Schering compound library consisting of 300,000 compounds for inhibitors of a nonreceptor tyrosine kinase. They chose to set up this study in realistic HTS scale to ensure statistical significance of the results. The findings clearly demonstrate that the choice of detection technology has no significant impact on hit finding, provided that assays are biochemically equivalent. Data concordance is up to 90%. The little differences in hit findings are caused by threshold setting but not by systematic differences between the technologies. The most significant difference between the compared techniques is that in the SPA format, more false-positive primary hits were obtained.

Sign in / Sign up

Export Citation Format

Share Document