Inhibiting Firefly Bioluminescence by Chalcones.

Chalcone refers to an aromatic ketone and an enone that constitutes the central core for various important biological compounds in drug discovery. Moreover, the firefly luciferase (Fluc) as the bioluminescent reporter has been widely used in life science research and high-throughput screening (HTS). However, Fluc might suffer from direct inhibition by HTS compounds resulting in the occurrence of "false positives.

cybLuc: An Effective Aminoluciferin Derivative for Deep Bioluminescence Imaging.

To enhance the efficiency of firefly luciferase/luciferin bioluminescence imaging, a series of N-cycloalkylaminoluciferins (cyaLucs) were developed by introducing lipophilic N-cycloalkylated substitutions. The experimental results demonstrate that these cyaLucs are effective substrates for native firefly luciferase (Fluc) and can produce elevated bioluminescent signals in vitro, in cellulo, and in vivo. It should be noted that, in animal studies, N-cyclobutylaminoluciferin (cybLuc) at 10 μM (0.

Discovery of Fluorescence Polarization Probe for the ELISA-Based Antagonist Screening of α-Adrenergic Receptors.

High-throughput screening (HTS) of ligand library to find new active molecules for G protein-coupled receptors is still a major interest, as well as an actual challenge. Fluorescence polarization (FP) assay portrays an essential role in HTS; however, in many cases, it was restricted by the absence of FP probes, the narrow measurement window, and low signal-to-noise (S/N) ratio. Herein, based on the modification of our previous probe (QFL), we discovered an FP probe (QGGFL) for α-adrenergic receptors (α-ARs), which has satisfactory fluorescence intensity, specific binding ability to receptors, and suitable fluorescence properties that were compatible with the filters in the FP system.

Novel bioluminescent coelenterazine derivatives with imidazopyrazinone C-6 extended substitution for Renilla luciferase.

Two series of novel coelenterazine analogues (alkynes and triazoles) with imidazopyrazinone C-6 extended substitution have been designed and synthesized successfully for the extension of bioluminescent substrates. After extensive evaluation, some compounds display excellent bioluminescence properties compared with DeepBlueC in cellulo, thus becoming potential molecules for bioluminescence techniques.

Real-Time Bioluminescence Imaging of Nitroreductase in Mouse Model.

Nitroreductase (NTR) is an endogenous reductase overexpressed in hypoxic tumors; however, its precise detection in living cells and animals remains a considerable challenge. Herein, we developed three reaction-based probes and a related bioluminescence assay for the real-time NTR detection. The high sensitivity and selectivity of probe 3, combined with its remarkable potential of bioluminescence imaging, affords a valuable approach for in vivo imaging of NTR in a tumor model mouse.

Quenching the firefly bioluminescence by various ions.

The luciferase reporter gene assay system is broadly applied in various biomedical aspects, including signaling pathway dissection, transcriptional activity analysis, and genetic toxicity testing. It significantly improves the experimental accuracy and reduces the experimental error by the addition of an internal control. In the current research, we discovered some specific ions that could selectively inhibit firefly luciferase while having a negligible effect on renilla luciferase in vitro in the dual-reporter gene assay.

Patterns of responding on a balloon analogue task reveal individual differences in overall risk-taking: choice between guaranteed and uncertain cash.

We explored the utility of analyzing within- and between-balloon response patterns on a balloon analogue task (BAT) in relation to overall risk scores, and to a choice between a small guaranteed cash reward and an uncertain reward of the same expected value. Young adults (n = 61) played a BAT, and then were offered a choice between $5 in cash and betting to win $0 to $15. Between groups, pumping was differentially influenced by explosions and by the number of successive unexploded balloons, with risk takers responding increasingly on successive balloons after an explosion.