Luciferase Signal Measurement
Luciferase Signal Measurement - Related Videos
02:36
The Luciferase Assay: A High-Throughput Assay to Measure Luminescent Signals Using Engineered Nanoluciferase System-Based Bioreporters
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2025
The video demonstrates the luciferase assay used to quantify luciferase-tagged proteins. The assay uses an engineered luciferase enzyme composed of a large fragment that binds with the small fragment, which is conjugated with a protein of interest. The bound subunits form an active enzyme that, in the presence of the substrate, releases a luminescent signal. This signal is then quantified using a luminometer.
03:38
Measuring Mycobacterium smegmatis Mistranslation Rates Using a GFP/Luciferase Reporter System
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2025
Source: Chen, Y., et al., Measurement of Specific Mycobacterial Mistranslation Rates with Gain-of-function Reporter Systems. J. Vis. Exp. (2019)This video demonstrates a method to quantify mistranslation in Mycobacterium smegmatis using an inducible GFP and secreted mutant luciferase reporter system. It shows how luminescence resulting from mistranslation is measured and compared to GFP fluorescence to evaluate the impact of a test molecule on translational accuracy.
10:13
A Multiplexed Luciferase-based Screening Platform for Interrogating Cancer-associated Signal Transduction in Cultured Cells
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Cited by 6 •
2013
Achieving a systems level understanding of cellular processes is a goal of modern-day cell biology. We describe here strategies for multiplexing luciferase reporters of various cellular function end-points to interrogate gene function using genome-scale RNAi libraries.
03:23
Measurement of the In Vivo Burden of Bacteria Expressing Luciferase in an Insect Larva
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2025
This video showcases the in vivo bacterial burden measurement using Bacillus Calmette-Guérin, BCG, lux-infected insect larvae. The process involves larval homogenization, treatment with a luciferase substrate, and bioluminescence measurement to determine relative light units that correlate with bacterial burden.
02:59
Luciferase Assay for Measuring γ-Secretase Activity in Human Cells
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2025
This video demonstrates the procedure of measuring γ-secretase activity in genetically modified human cells using a tetracycline-inducible system. The process involves inducing APP gene expression with tetracycline, generating amyloid-β peptides, and activating luciferase production. The bioluminescence resulting from the luciferase-substrate reaction is then measured, reflecting γ-secretase activity.
FAQs
During luciferase signal measurement, the reporter enzyme uses its luciferin substrate and required cofactors to drive a light-producing reaction. A luminometer detects the emitted photons and reports them as relative light units, or RLU. The resulting value links luciferase activity to reporter output, allowing investigators to compare activity across biological samples under defined experimental conditions.
Luciferin and the required cofactors support the reaction that produces the measurable light signal. Their presence allows luciferase activity to be translated into emitted photons for luminometer detection. Consequently, the recorded RLU depends on the reporter reaction functioning under the assay conditions, making these reaction components essential when comparing biological samples or experimental treatments.
Controls and normalization make comparisons more meaningful by providing a reference for interpreting signal differences between conditions. Without them, a change in relative light units may be difficult to associate with altered gene expression or a cellular response. Appropriate normalization therefore supports quantitative evaluation of promoter activity, signaling effects, transcriptional regulation, and treatment responses.
A basic workflow applies the luciferin substrate and required cofactors to the biological sample, permits the luciferase reaction to produce light, and records the emitted signal with a luminometer. Researchers then express the measurement as relative light units and compare samples using appropriate controls and normalization. This sequence supports rapid quantitative assessment while requiring only low sample amounts.
The method can be used to examine promoter activity, transcriptional regulation, signaling pathways, and responses to experimental treatments. In each case, luciferase activity serves as a reporter readout that helps quantify differences between biological conditions. This makes the assay useful for connecting changes in cellular processes with measurable changes in emitted light.
Its rapid signal generation and typically low sample requirement allow researchers to measure reporter activity across multiple biological conditions. Relative light units provide a numerical basis for comparison, while appropriate controls and normalization help account for experimental differences. The approach is therefore suited to evaluating whether treatments or regulatory conditions alter gene expression-related processes or cellular signaling.