In Vivo Simultaneous Analysis of Gene Expression by Dual-Color Luciferases in Caenorhabditis elegans

Quantitative Analysis of Bioluminescence Optical Signal

Bioluminescence is light emission based on the luciferin-luciferase enzymatic reaction in living organisms. Optical signals from bioluminescence (BL) reactions are available for bioanalysis and bioreporters for gene expression, in vitro, in vivo, and ex vivo bioimaging, immunoassay, and other applications. Although there are numerous bioanalysis methods based on BL signal measurements, the BL signal is measured as a relative value, and not as an absolute value. Recently, some approaches have been established to completely quantify the BL signal, resulting in, for instance, the redetermination of the quantum yield of the BL reaction and counting the photon number of the BL signal at the single-cell level. Reliable and reproducible understanding of biological events in the bioanalysis and bioreporter fields can be achieved by means of standardized absolute optical signal measurements, which is described in an International Organization for Standardization (ISO) document.

Bioluminescent and Fluorescent Proteins: Molecular Mechanisms and Modern Applications

Light emission by living organisms in the visible spectrum range is called bioluminescence [...].

A Ratiometric Dual Color Luciferase Reporter for Fast Characterization of Transcriptional Regulatory Elements in Plants

Plant synthetic biology requires precise characterization of genetic elements to construct complex genetic circuits that can improve plant traits or confer them with new characteristics. Transcriptional reporter assays are essential to quantify the effect of gene expression regulator elements. Additionally, transcriptional reporter systems are a key tool in understanding control of gene expression in biology. In this work, we construct and characterize a dual color luciferase ratiometric reporter system that possesses several advantages over currently used reporters. It is ratiometric, thus reducing variability and increasing consistency between experiments; it is fast, as both reporters can be measured at the same time in a single reaction, and it is less expensive to perform than current dual luciferase reporter assays. We have validated our system quantifying the transcriptional capability of a panel of promoters and terminators commonly used in synthetic biology with a broad range of expression magnitudes, and in a biologically relevant system, nitrate response.

Emerging tools for bioluminescence imaging

Bioluminescence (BL) relies on the enzymatic reaction between luciferase, a substrate conventionally named luciferin, and various cofactors. BL imaging has become a widely used technique to interrogate gene expression and cell fate, both in small and large animal models of research. Recent developments include the generation of improved luciferase-luciferin systems for deeper and more sensitive imaging as well as new caged luciferins to report on enzymatic activity and other intracellular functions. Here, we critically evaluate the emerging tools for BL imaging aiming to provide the reader with an updated compendium of the latest developments (2018-2020) and their notable applications.

How to Select Firefly Luciferin Analogues for In Vivo Imaging

Bioluminescence reactions are widely applied in optical in vivo imaging in the life science and medical fields. Such reactions produce light upon the oxidation of a luciferin (substrate) catalyzed by a luciferase (enzyme), and this bioluminescence enables the quantification of tumor cells and gene expression in animal models. Many researchers have developed single-color or multicolor bioluminescence systems based on artificial luciferin analogues and/or luciferase mutants, for application in vivo bioluminescence imaging (BLI). In the current review, we focus on the characteristics of firefly BLI technology and discuss the development of luciferin analogues for high-resolution in vivo BLI. In addition, we discuss the novel luciferin analogues TokeOni and seMpai, which show potential as high-sensitivity in vivo BLI reagents.