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Magnetic Control of Biogenic Micro-Mirror
Published in Shoogo Ueno, Bioimaging, 2020
Uric acid crystals are also utilized as optical materials by insects such as fireflies. The luciferase-luciferin reaction that generates their light emission occurs in a photochemical reaction chamber that is thought to have precise light-controlling units [46,47]. One unit is a spherical uric acid crystal that can be observed inside the lantern bud of the fireflies [48] and diffuses light from the emission chamber. The intensity of firefly light emission was suppressed and modulated when exposed to magnetic fields up to 14 T [49,50]. Hence, this section focuses on the correlation between magnetic fields and light reflection in uric acid crystals.
Analyzing the GPCR Function of Polycystin-1
Published in Jinghua Hu, Yong Yu, Polycystic Kidney Disease, 2019
Stephen C. Parnell, Robin L. Maser, Brenda S. Magenheimer, James P. Calvet
The procedures for demonstrating the ability of various PC1 C-tail constructs and Gα subunits to activate an NFAT promoter-reporter are provided here and outlined below. HEK293T cells are transiently cotransfected with an NFAT-responsive promoter-firefly luciferase reporter construct (100 ng/well/6-well plate) and a control Renilla luciferase construct (1.5 ng/well) together with 500 ng/well of either the control sIg-0 or one of various PC1 C-tail deletion constructs (e.g., PC1-LT222, PC1-HT193, PC1-AT120, or PC1-LS111). The final DNA amount is brought to 3 μg/well using pBS DNA. The cells are harvested and lysed 24 h posttransfection using Promega 1+ Passive Lysis Buffer. Luciferase activity is then measured using the Dual-Luciferase Reporter Assay System (Promega). The Renilla luciferase values for the wells within an individual 3-well experiment are used to correct firefly luciferase values. It is important to normalize values with a control construct that does not respond to PC1, such as the pCis-CK plasmid, which should not have activity. Anti-human IgG Western blots demonstrate expression levels of the various fusion proteins.
Optical-CT Imaging
Published in George C. Kagadis, Nancy L. Ford, Dimitrios N. Karnabatidis, George K. Loudos, Handbook of Small Animal Imaging, 2018
Xueli Chen, Dongmei Chen, Fenglin Liu, Wenxiang Cong, Ge Wang, Jimin Liang
Bioluminescent light is produced from the expression of luciferase enzymes, such as firefly luciferase, Renilla luciferase, and jellyfish luciferase. Cells encoded with the luciferase enzymes can serve as bioluminescent probes, which allow bioluminescent light emission. The BLT technique uses the luciferase enzyme gene as a reporter (Contag and Bachmann 2002). Oxidation of luciferin, which is injected into the animal, leads to the emission of bioluminescent light and occurs only in cells in which the luciferase enzyme is expressed by the reporter gene. The major attraction of this approach is that although absolute light levels are low, signal is produced only where luciferase is present, leading to extremely low background signals (Troy et al. 2004). BLT was first proposed by Wang’s group in 2003 (Wang et al. 2003). In mathematics, it is an inverse source problem. Based on an accurate light transport model, BLT aims to reconstruct the 3D spatial distribution and concentration of the bioluminescent probes inside a small living animal.
Advances in luminescence-based technologies for drug discovery
Published in Expert Opinion on Drug Discovery, 2023
Bolormaa Baljinnyam, Michael Ronzetti, Anton Simeonov
Chemiluminescence is a phenomenon of light emission derived from a chemical reaction when chemically excited electrons return to the ground state. Bioluminescence, a type of chemiluminescence, refers to the photon-emitting processes occurring in living organisms often used to ward off predators, attract prey, or as a means of communication. The machinery responsible for bioluminescence is evolutionarily conserved among marine creatures such as bacteria, planktons, algae, crustaceans, squids, and fish but is also found in terrestrial organisms like bacteria, fungi, worms, and insects [1,2]. These bioluminescent reactions rely on enzymes, termed luciferases, that catalyze the oxidation of a family of substrates called luciferins, resulting in the emission of a photon. The luciferase family of proteins, as well as their luciferin substrates, are as structurally diverse as the organisms from which they are derived, each with their own fingerprint wavelength and quantum yield.
Sauropus brevipes ethanol extract negatively regulates inflammatory responses in vivo and in vitro by targeting Src, Syk and IRAK1
Published in Pharmaceutical Biology, 2021
Ji Hye Kim, Jae Gwang Park, Yo Han Hong, Kon Kuk Shin, Jin Kyeong Kim, Young-Dong Kim, Ki Dong Yoon, Kyung-Hee Kim, Byong Chul Yoo, Gi-Ho Sung, Jae Youl Cho
Effect of Sb-EE on inflammatory gene expression and transcriptional factors. (A) To verify the effect of Sb-EE on inflammatory biomarker expression, RAW264.7 cells were pre-treated with Sb-EE, then stimulated with LPS (1 µg/mL) for 6 h. mRNA expression of iNOS, COX-2 and TNF-α was analysed by semi-quantitative RT-PCR. (B, C) To validate the effect of Sb-EE on the transcriptional activity of NF-κB and AP-1, a luciferase assay was performed. HEK 293 cells were transfected with NF-κB-Luc (B) or AP-1-Luc (C) genes, and Flag-MyD88 or CFP-TRIF were additionally overexpressed to activate transcription of NF-κB-Luc and AP-1-Luc genes. Then, HEK 293 cells were treated with Sb-EE (0–200 μg/mL) for 24 h. Luciferase activity was measured using a luminometer. (D) To analyse nuclear translocation of transcription factor subunits, Sb-EE (200 μg/mL) pre-treated RAW264.7 cells were stimulated with LPS for the indicated times. Then, the levels of AP-1 (c-Fos and c-Jun) and NF-κB subunits (p65 and p50) in nuclear lysate were determined by immunoblotting. Lamin A/C was utilized as a loading control. All data are presented as the mean ± SD of experiments. ##p < 0.01 compared to the normal group, and *p < 0.05 and **p < 0.01 compared to the control group (LPS-alone group in (A, D), and MyD88/TRIF-alone group in (B, C)).
Characterization of MW06, a human monoclonal antibody with cross-neutralization activity against both SARS-CoV-2 and SARS-CoV
Published in mAbs, 2021
Wen Jiang, Junchao Wang, Shasha Jiao, Chenjian Gu, Wei Xu, Ben Chen, Rongjuan Wang, Huilin Chen, Youhua Xie, An Wang, Gang Li, Dadi Zeng, Jinchao Zhang, Min Zhang, Shuang Wang, Mingzhu Wang, Xun Gui
For the pseudovirus neutralization assay, 100 µL of mAbs at different concentrations were mixed with 50 µL supernatant containing ~1000 TCID50 SARS-CoV-2 or SARS-CoV pseudovirus. The mixture was incubated at 37°C for 1 hour, supplied with 5% CO2. 100 µL of Huh-7 cell or Vero cell suspension (2 × 105 cells/mL) was then added to the mixtures of pseudoviruses and mAbs for an additional 24-hour incubation at 37°C. Then, 150 μL of supernatant was removed, and 100 μL luciferase detecting regents (Cat. 6066769, PerkinElmer) was added to each well. After 2 minutes of incubation, each well was mixed 6–8 times by pipetting, and 150 μL of the mixture was transferred to a new microplate. Luciferase activity was measured using a microplate luminometer (SpectraMax L, Molecular Devices). The 50% neutralization titer (NT50) was calculated using GraphPad Prism 8.2.1.