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1.
Methods Mol Biol ; 2854: 19-28, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39192114

RESUMO

The classic dual luciferase reporter assay has been widely used to rapidly and accurately determine the transcriptional activity of a given promoter induced by certain signal pathways in the cells. In particular, the sensitive characteristics of luciferase highlight its significance in many experiments, such as weak promoter analysis, transfection studies using small amounts of DNA, and detection in cell lines with low transfection efficiency. This chapter presents detailed information and experimental procedures for measuring interferon (IFN)-induced Interferon-Stimulated Response Element (ISRE) promoter activity using the dual luciferase reporter assay.


Assuntos
Genes Reporter , Interferons , Luciferases , Regiões Promotoras Genéticas , Elementos de Resposta , Transdução de Sinais , Humanos , Interferons/metabolismo , Interferons/genética , Luciferases/metabolismo , Luciferases/genética , Transfecção , Animais
2.
Methods Mol Biol ; 2854: 127-141, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39192125

RESUMO

Luciferase reporter systems are commonly used in scientific research to investigate a variety of biological processes, including antiviral innate immunity. These systems employ the use of luciferase enzymes derived from organisms such as fireflies or renilla reniformis, which emit light upon reaction with a substrate. In the context of antiviral innate immunity, the luciferase reporter systems offer a noninvasive and highly sensitive approach for real-time monitoring of immune responses in vitro and in vivo, enabling researchers to delve into the intricate interactions and signaling pathways involved in host-virus dynamic interactions. Here, we describe the methods of the promoter-luciferase reporter and enhancer-luciferase reporter, which provide insights into the transcriptional and post-transcriptional regulation of antiviral innate immunity. Additionally, we outline the split-luciferase complementary reporter method, which was designed to explore protein-protein interactions associated with antiviral immunity. These methodologies offer invaluable knowledge regarding the molecular mechanisms underlying antiviral immune pathways and have the potential to support the development of effective antiviral therapies.


Assuntos
Genes Reporter , Imunidade Inata , Luciferases , Humanos , Luciferases/metabolismo , Luciferases/genética , Animais , Interferons/metabolismo , Interferons/imunologia , Regiões Promotoras Genéticas , Antivirais/farmacologia , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/genética
3.
Sci Rep ; 14(1): 19412, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169077

RESUMO

In the past decade, the exploration of genetic resources in rice has significantly enhanced the efficacy of rice breeding. However, the exploration of genetic resources is hindered by the identification of candidate genes. To expedite the identification of candidate genes, this study examined tapetum programmed cell death-related genes OsiWAK1, OsPDT1, EAT1, TDR, and TIP2 to assess the efficacy of the Dual-Luciferase (Dual-LUC) assay in rapidly determining gene relationships. The study found that, in the Dual-LUC assay, OsiWAK1 and its various recombinant proteins exhibit comparable activation abilities on the EAT1 promoter, potentially indicating a false positive. However, the Dual-LUC assay can reveal that OsiWAK1 impacts both the function of its upstream regulatory factor OsPDT1 and the TDR/TIP2 transcription complex. By rapidly studying the relationship between diverse candidate genes and regulatory genes in a well-known trait via the Dual-LUC assay, this study provides a novel approach to expedite the determination of candidate genes such as genome-wide association study.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Luciferases/genética , Luciferases/metabolismo , Regiões Promotoras Genéticas
4.
In Vivo ; 38(5): 2122-2125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39187316

RESUMO

BACKGROUND/AIM: In vivo imaging with luciferase-luciferin has been limited by the inability to visualize the low emitted light, with the signal quantified only by photon counting using a cumbersome highly-cooled CCD camera in a dark room. In the present study, we demonstrate direct visualization of the luciferase-luciferin signal from an orthotopic lung cancer in a nude-mouse xenograft model with a sensitive low-light camera and optics. MATERIALS AND METHODS: Mouse Lewis-lung carcinoma cells expressing luciferase (LL/2-Luc2) were injected transcutaneously into the lung of a nude mouse. One week later after cell injection, luciferase imaging for emission at 560 nm was performed using the UVP Biospectrum Advanced system after i.v. injection of D-luciferin potassium salt. The intensity of the visualized light was measured and quantified with the instrument. RESULTS: A week following the implantation of LL/2-Luc2 cells in nude mice, the luciferase-luciferin signal from LL/2-Luc2 tumors in the lung was sufficiently visible through the skin to produce true images. At fifteen minutes, the intensity peaked and then progressively dropped due to clearance of luciferin from the tumor. CONCLUSION: Using the UVP Biospectrum Advanced system we demonstrated non-invasive visualization of true images from luciferase-luciferin signals from an orthotopic lung-cancer mouse model. The luciferase-luciferin emitted light was directly visible through the skin which is a major improvement over previous photon counting to detect the luciferase-luciferin signal.


Assuntos
Luciferases , Medições Luminescentes , Neoplasias Pulmonares , Camundongos Nus , Animais , Camundongos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Luciferases/metabolismo , Luciferases/genética , Linhagem Celular Tumoral , Medições Luminescentes/métodos , Modelos Animais de Doenças , Humanos , Xenoenxertos , Benzotiazóis , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Anal Chim Acta ; 1322: 343057, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39182992

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the subsequent pandemic have led to devastating public health and economic losses. The development of highly sensitive, rapid and inexpensive methods to detect and monitor coronaviruses is essential for family diagnosis, preventing infections, choosing treatments and programs and laying the technical groundwork for viral diagnosis. This study established one-step immunoassays for rapid and sensitive detection of SARS-CoV-2 by using a single-chain variable fragment (scFv) fused to alkaline phosphatase (AP) or NanoLuc (NLuc) luciferase. First, a high-affinity scFv antibody specific to the SARS-CoV-2 nucleocapsid (N) protein was screened from hybridoma cells-derived and phage-displayed library. Next, prokaryotic expression of the scFv-AP and scFv-NLuc fusion proteins were induced, leading to excellent antibody binding properties and enzyme catalytic activities. The scFv-AP fusion had a detection limit of 3 pmol per assay and was used to produce eye-readable biosensor readouts. Moreover, the scFv-NLuc protein was applied in a highly sensitive luminescence immunoassay, achieving a detection limit lower than 0.1 pmol per assay. Therefore, the scFv-AP and scFv-NLuc fusion proteins can be applied for the rapid and simple diagnosis of SARS-CoV-2 to safeguard human health and provide guidance for the detection of other pathogenic viruses.


Assuntos
Fosfatase Alcalina , COVID-19 , Luciferases , SARS-CoV-2 , Anticorpos de Cadeia Única , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/química , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Fosfatase Alcalina/química , Humanos , Luciferases/química , Luciferases/genética , COVID-19/diagnóstico , COVID-19/virologia , Limite de Detecção , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/imunologia , Biblioteca de Peptídeos , Técnicas Biossensoriais/métodos , Imunoensaio/métodos
6.
Int J Mol Sci ; 25(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39125775

RESUMO

Multimodality reporter gene imaging combines the sensitivity, resolution and translational potential of two or more signals. The approach has not been widely adopted by the animal imaging community, mainly because its utility in this area is unproven. We developed a new complementation-based reporter gene system where the large component of split NanoLuc luciferase (LgBiT) presented on the surface of cells (TM-LgBiT) interacts with a radiotracer consisting of the high-affinity complementary HiBiT peptide labeled with a radionuclide. Radiotracer uptake could be imaged in mice using SPECT/CT and bioluminescence within two hours of implanting reporter-gene-expressing cells. Imaging data were validated by ex vivo biodistribution studies. Following the demonstration of complementation between the TM-LgBiT protein and HiBiT radiotracer, we validated the use of the technology in the highly specific in vivo multimodal imaging of cells. These findings highlight the potential of this new approach to facilitate the advancement of cell and gene therapies from bench to clinic.


Assuntos
Genes Reporter , Luciferases , Animais , Camundongos , Luciferases/metabolismo , Luciferases/genética , Humanos , Distribuição Tecidual , Imagem Óptica/métodos , Medições Luminescentes/métodos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Cintilografia/métodos , Linhagem Celular Tumoral
7.
Protein Sci ; 33(8): e5115, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39023083

RESUMO

Gaussia luciferase (GLuc) is one of the most luminescent luciferases known and is widely used as a reporter in biochemistry and cell biology. During catalysis, GLuc undergoes inactivation by irreversible covalent modification. The mechanism by which GLuc generates luminescence and how it becomes inactivated are however not known. Here, we show that GLuc unlike other enzymes has an extensively disordered structure with a minimal hydrophobic core and no apparent binding pocket for the main substrate, coelenterazine. From an alanine scan, we identified two Arg residues required for light production. These residues separated with an average of about 22 Å and a major structural rearrangement is required if they are to interact with the substrate simultaneously. We furthermore show that in addition to coelenterazine, GLuc also can oxidize furimazine, however, in this case without production of light. Both substrates result in the formation of adducts with the enzyme, which eventually leads to enzyme inactivation. Our results demonstrate that a rigid protein structure and substrate-binding site are no prerequisites for high enzymatic activity and specificity. In addition to the increased understanding of enzymes in general, the findings will facilitate future improvement of GLuc as a reporter luciferase.


Assuntos
Luciferases , Luciferases/química , Luciferases/metabolismo , Luciferases/genética , Animais , Luminescência , Copépodes/enzimologia , Modelos Moleculares , Imidazóis/química , Imidazóis/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/metabolismo , Pirazinas/química , Pirazinas/metabolismo
8.
Nat Commun ; 15(1): 5609, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965228

RESUMO

Epilepsy affects 1% of the general population and 30% of patients are resistant to antiepileptic drugs. Although optogenetics is an efficient antiepileptic strategy, the difficulty of illuminating deep brain areas poses translational challenges. Thus, the search of alternative light sources is strongly needed. Here, we develop pH-sensitive inhibitory luminopsin (pHIL), a closed-loop chemo-optogenetic nanomachine composed of a luciferase-based light generator, a fluorescent sensor of intracellular pH (E2GFP), and an optogenetic actuator (halorhodopsin) for silencing neuronal activity. Stimulated by coelenterazine, pHIL experiences bioluminescence resonance energy transfer between luciferase and E2GFP which, under conditions of acidic pH, activates halorhodopsin. In primary neurons, pHIL senses the intracellular pH drop associated with hyperactivity and optogenetically aborts paroxysmal activity elicited by the administration of convulsants. The expression of pHIL in hippocampal pyramidal neurons is effective in decreasing duration and increasing latency of pilocarpine-induced tonic-clonic seizures upon in vivo coelenterazine administration, without affecting higher brain functions. The same treatment is effective in markedly decreasing seizure manifestations in a murine model of genetic epilepsy. The results indicate that pHIL represents a potentially promising closed-loop chemo-optogenetic strategy to treat drug-refractory epilepsy.


Assuntos
Epilepsia , Neurônios , Optogenética , Animais , Concentração de Íons de Hidrogênio , Camundongos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Epilepsia/fisiopatologia , Epilepsia/metabolismo , Epilepsia/tratamento farmacológico , Humanos , Convulsões/tratamento farmacológico , Convulsões/fisiopatologia , Convulsões/metabolismo , Halorrodopsinas/metabolismo , Halorrodopsinas/genética , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Masculino , Luciferases/metabolismo , Luciferases/genética , Células Piramidais/metabolismo , Células Piramidais/efeitos dos fármacos , Imidazóis/farmacologia , Pilocarpina/farmacologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Células HEK293 , Pirazinas
9.
Appl Environ Microbiol ; 90(8): e0071724, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39016615

RESUMO

Mechanistic investigations are of paramount importance in elucidating the modes of action of antibiotics and facilitating the discovery of novel drugs. We reported a luciferase-based reporter system using bacterial cells to unveil mechanisms of antimicrobials targeting transcription and translation. The reporter gene Nluc encoding NanoLuciferase (NanoLuc) was integrated into the genome of the Gram-positive model organism, Bacillus subtilis, to generate a reporter strain BS2019. Cellular transcription and translation levels were assessed by quantifying the amount of Nluc mRNA as well as the luminescence catalyzed by the enzyme NanoLuc. We validated this system using three known inhibitors of transcription (rifampicin), translation (chloramphenicol), and cell wall synthesis (ampicillin). The B. subtilis reporter strain BS2019 successfully revealed a decline in Nluc expression by rifampicin and NanoLuc enzyme activity by chloramphenicol, while ampicillin produced no observable effect. The assay was employed to characterize a previously discovered bacterial transcription inhibitor, CUHK242, with known antimicrobial activity against drug-resistant Staphylococcus aureus. Production of Nluc mRNA in our reporter BS2019 was suppressed in the presence of CUHK242, demonstrating the usefulness of the construct, which provides a simple way to study the mechanism of potential antibiotic candidates at early stages of drug discovery. The reporter system can also be modified by adopting different promoters and reporter genes to extend its scope of contribution to other fields of work. IMPORTANCE: Discovering new classes of antibiotics is desperately needed to combat the emergence of multidrug-resistant pathogens. To facilitate the drug discovery process, a simple cell-based assay for mechanistic studies is essential to characterize antimicrobial candidates. In this work, we developed a luciferase-based reporter system to quantify the transcriptional and translational effects of potential compounds and validated our system using two currently marketed drugs. Reporter strains generated in this study provide readily available means for identifying bacterial transcription inhibitors as prospective novel antibacterials. We also provided a series of plasmids for characterizing promoters under various conditions such as stress.


Assuntos
Antibacterianos , Bacillus subtilis , Genes Reporter , Luciferases , Bacillus subtilis/genética , Bacillus subtilis/efeitos dos fármacos , Antibacterianos/farmacologia , Luciferases/genética , Testes de Sensibilidade Microbiana
10.
Viruses ; 16(7)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39066165

RESUMO

Foot-and-mouth disease virus (FMDV) is a highly contagious virus that affects cloven-hoofed animals and causes severe economic losses in the livestock industry. Given that this high-risk pathogen has to be handled in a biosafety level (BSL)-3 facility for safety reasons and the limited availability of BSL-3 laboratories, experiments on FMDV call for more attention. Therefore, we aimed to develop an FMDV experimental model that can be handled in BSL-2 laboratories. The NanoBiT luciferase (Nano-luc) assay is a well-known assay for studying protein-protein interactions. To apply the NanoBiT split luciferase assay to the diagnosis and evaluation of FMD, we developed an inactivated HiBiT-tagged Asia1 Shamir FMDV (AS-HiBiT), a recombinant Asia1 shamir FMDV with HiBiT attached to the VP1 region of Asia1 shamir FMDV. In addition, we established LgBiT-expressing LF-BK cell lines, termed LgBit-LF-BK cells. It was confirmed that inactivated AS-HiBiT infected LgBiT-LF-BK cells and produced a luminescence signal by binding to the intracellular LgBiT of LgBiT-LF-BK cells. In addition, the luminescence signal became stronger as the number of LgBiT-LF-BK cells increased or the concentration of inactivated AS-HiBiT increased. Moreover, we confirmed that inactivated AS-HiBiT can detect seroconversion in sera positive for FMDV-neutralizing antibodies. This NanoBiT split luciferase assay system can be used for the diagnosis and evaluation of FMD and expanded to FMD-like virus models to facilitate the evaluation of FMDV vaccines and antibodies.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Linhagem Celular , Febre Aftosa/diagnóstico , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Luciferases/genética , Luciferases/metabolismo
11.
ACS Synth Biol ; 13(8): 2402-2411, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39023433

RESUMO

Plastid engineering offers the potential to carry multigene traits in plants; however, it requires reliable genetic parts to balance expression. The difficulty of chloroplast transformation and slow plant growth makes it challenging to build plants just to characterize genetic parts. To address these limitations, we developed a high-yield cell-free system from Nicotiana tabacum chloroplast extracts for prototyping genetic parts. Our cell-free system uses combined transcription and translation driven by T7 RNA polymerase and works with plasmid or linear template DNA. To develop our system, we optimized lysis, extract preparation procedures (e.g., runoff reaction, centrifugation, and dialysis), and the physiochemical reaction conditions. Our cell-free system can synthesize 34 ± 1 µg/mL luciferase in batch reactions and 60 ± 4 µg/mL in semicontinuous reactions. We apply our batch reaction system to test a library of 103 ribosome binding site (RBS) variants and rank them based on cell-free gene expression. We observe a 1300-fold dynamic range of luciferase expression when normalized by maximum mRNA expression, as assessed by the malachite green aptamer. We also find that the observed normalized gene expression in chloroplast extracts and the predictions made by the RBS Calculator are correlated. We anticipate that chloroplast cell-free systems will increase the speed and reliability of building genetic systems in plant chloroplasts for diverse applications.


Assuntos
Sistema Livre de Células , Cloroplastos , Nicotiana , Cloroplastos/genética , Cloroplastos/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Engenharia Genética/métodos , Luciferases/genética , Luciferases/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Ribossomos/metabolismo , Ribossomos/genética , Sítios de Ligação , Transcrição Gênica/genética , Proteínas Virais
12.
Bioorg Med Chem ; 110: 117814, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981217

RESUMO

Oligonucleotide therapeutics, particularly antisense oligonucleotides (ASOs), have emerged as promising candidates in drug discovery. However, their effective delivery to the target tissues and cells remains a challenge, necessitating the development of suitable drug delivery technologies for ASOs to enable their practical application. In this study, we synthesized a library of chemically modified dipeptide-ASO conjugates using a recent synthetic method based on the Ugi reaction. We then conducted in vitro screening of this library using luciferase-expressing cell lines to identify ligands capable of enhancing ASO activity. Our findings suggest that N-(4-nitrophenoxycarbonyl)glycine may interact with the thiophosphate moiety of the phosphorothioate-modification in ASO. Through our screening efforts, we identified two ligands that modestly reduced luciferase luminescence in a cell type-selective manner. Furthermore, quantification of luciferase mRNA levels revealed that one of these promising dipeptide-ASO conjugates markedly suppressed luciferase RNA levels through its antisense effect in prostate-derived DU-145 cells compared to the ASOs without ligand modification.


Assuntos
Dipeptídeos , Oligonucleotídeos Antissenso , Dipeptídeos/química , Dipeptídeos/síntese química , Dipeptídeos/farmacologia , Humanos , Ligantes , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/síntese química , Oligonucleotídeos Antissenso/farmacologia , Linhagem Celular Tumoral , Estrutura Molecular , Relação Estrutura-Atividade , Luciferases/metabolismo , Luciferases/genética , Relação Dose-Resposta a Droga
13.
Int J Mol Sci ; 25(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39000448

RESUMO

Bioluminescence imaging (BLI) is an indispensable technique for visualizing the dynamics of diverse biological processes in mammalian animal models, including cancer, viral infections, and immune responses. However, a critical scientific challenge remains: non-invasively visualizing homeostatic and disease mechanisms in freely moving animals to understand the molecular basis of exercises, social behavior, and other phenomena. Classical BLI relies on prolonged camera exposure to accumulate the limited number of photons that traveled from deep tissues in anesthetized or constrained animals. Recent advancements in synthetic bioluminescence reactions, utilizing artificial luciferin-luciferase pairs, have considerably increased the number of detectable photons from deep tissues, facilitating high-speed BLI to capture moving objects. In this review, I provide an overview of emerging synthetic bioluminescence reactions that enable the non-invasive imaging of freely moving animals. This approach holds the potential to uncover unique physiological processes that are inaccessible with current methodologies.


Assuntos
Medições Luminescentes , Animais , Medições Luminescentes/métodos , Luciferases/metabolismo , Luciferases/genética , Humanos
14.
Cells ; 13(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39056749

RESUMO

BACKGROUND: Metastasis is the main cause of cancer-related deaths, but efficient targeted therapies against metastasis are still missing. Major gaps exist in our understanding of the metastatic cascade, as existing methods cannot combine sensitivity, robustness, and practicality to dissect cancer progression. Addressing this issue requires improved strategies to distinguish early metastatic colonization from metastatic outgrowth. METHODS: Luciferase-labelled MDA-MB-231, MCF7, and 4T1 breast cancer cells were spiked into samples from tumour-naïve mice to establish the limit of detection for disseminated tumour cells. Luciferase-labelled breast cancer cells (±unlabelled cancer-associated fibroblasts; CAFs) were orthotopically implanted in immunocompromised mice. An ex vivo luciferase assay was used to quantify tumour cell dissemination. RESULTS: In vitro luciferase assay confirmed a linear and positive correlation between cancer cell numbers and the bioluminescence detected at single cell level in blood, brain, lung, liver, and mammary fat pad samples. Remarkably, single luciferase-labelled cancer cells were detectable in all of these sites, as the bioluminescence quantified in the analysed samples was substantially higher than background levels. Ex vivo, circulating tumour cells, metastasis, and tumour self-seeding were detected in all samples from animals implanted with highly metastatic luciferase-labelled MDA-MB-231 cells. In turn, detection of poorly metastatic luciferase-labelled MCF7 cells was scarce but significantly enhanced upon co-implantation with CAFs as early as 20 days after the experiment was initiated. CONCLUSIONS: These results demonstrate the feasibility of using an ultrasensitive luciferase-based method to dissect the mechanisms of early metastatic colonization to improving the development of antimetastatic therapies.


Assuntos
Neoplasias da Mama , Metástase Neoplásica , Células Neoplásicas Circulantes , Animais , Neoplasias da Mama/patologia , Neoplasias da Mama/sangue , Feminino , Camundongos , Humanos , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Modelos Animais de Doenças , Linhagem Celular Tumoral , Detecção Precoce de Câncer/métodos , Luciferases/metabolismo
15.
ACS Sens ; 9(7): 3489-3495, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38973210

RESUMO

The ability of proteins to sense and transmit mechanical forces underlies many biological processes, but characterizing these forces in biological systems remains a challenge. Existing genetically encoded force sensors typically rely on fluorescence or bioluminescence resonance energy transfer (FRET or BRET) to visualize tension. However, these force sensing modules are relatively large, and interpreting measurements requires specialized image analysis and careful control experiments. Here, we report a compact molecular tension sensor that generates a bioluminescent signal in response to tension. This sensor (termed PILATeS) makes use of the split NanoLuc luciferase and consists of the H. sapiens titin I10 domain with the insertion of a 10-15 amino acid tag derived from the C-terminal ß-strand of NanoLuc. Mechanical load across PILATeS mediates exposure of this tag to recruit the complementary split NanoLuc fragment, resulting in force-dependent bioluminescence. We demonstrate the ability of PILATeS to report biologically meaningful forces by visualizing forces at the interface between integrins and extracellular matrix substrates. We further use PILATeS as a genetically encoded sensor of tension experienced by the mechanosensing protein vinculin. We anticipate that PILATeS will provide an accessible means of visualizing molecular-scale forces in biological systems.


Assuntos
Técnicas Biossensoriais , Luciferases , Medições Luminescentes , Humanos , Luciferases/química , Luciferases/metabolismo , Luciferases/genética , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Conectina/química , Conectina/metabolismo , Vinculina/metabolismo , Vinculina/química
16.
J Vis Exp ; (208)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949387

RESUMO

The repair of DNA double strand breaks (DSBs) is crucial for the maintenance of genome stability and cell viability. DSB repair (DSBR) in cells is mediated through several mechanisms: homologous recombination (HR), non-homologous end joining (NHEJ), microhomology-mediated end joining (MMEJ), and single strand annealing (SSA). Cellular assays are essential to measure the proficiency and modulation of these pathways in response to various stimuli. Here, we present a suite of extrachromosomal reporter assays that each measure the reconstitution of a nanoluciferase reporter gene by one of the four major DSBR pathways in cells. Upon transient transfection into cells of interest, repair of pathway-specific reporter substrates can be measured in under 24 h by the detection of Nanoluciferase (NanoLuc) luminescence. These robust assays are quantitative, sensitive, titratable, and amenable to a high-throughput screening format. These properties provide broad applications in DNA repair research and drug discovery, complementing the currently available toolkit of cellular DSBR assays.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Reparo do DNA/fisiologia , Humanos , Ensaios de Triagem em Larga Escala/métodos , Medições Luminescentes/métodos , Genes Reporter , Luciferases/genética , Luciferases/metabolismo
17.
Biosens Bioelectron ; 261: 116454, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38875866

RESUMO

Several organ-on-chip and cell-on-chip devices have been reported, however, their main drawback is that they are not interoperable (i.e., they have been fabricated with customized equipment, thus cannot be applied in other facilities, unless having the same setup), and require cell-culture facilities and benchtop instrumentation. As a consequence, results obtained with such devices do not generally comply with the principles of findability, accessibility, interoperability, and reusability (FAIR). To overcome such limitation, leveraging cost-effective 3D printing we developed a bioluminescent tissue on-a-chip device that can be easily implemented in any laboratory. The device enables continuous monitoring of cell co-cultures expressing different bioluminescent reporter proteins and, thanks to the implementation of new highly bioluminescent luciferases having high pH and thermal stability, can be monitored via smartphone camera. Another relevant feature is the possibility to insert the chip into a commercial 24-well plate for use with standard benchtop instrumentation. The suitability of this device for 3D cell-based biosensing for monitoring activation of target molecular pathways, i.e., the inflammatory pathway via nuclear factor kappa-B (NF-κB) activation, and general cytotoxicity is here reported showing similar analytical performance when compared to conventional 3D cell-based assays performed in 24-well plates.


Assuntos
Técnicas Biossensoriais , Dispositivos Lab-On-A-Chip , Medições Luminescentes , Smartphone , Técnicas Biossensoriais/instrumentação , Smartphone/instrumentação , Humanos , Medições Luminescentes/instrumentação , Medições Luminescentes/economia , Desenho de Equipamento , Impressão Tridimensional/instrumentação , Luciferases/química , Luciferases/metabolismo , Luciferases/genética
18.
Dent Mater ; 40(9): 1313-1321, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38876827

RESUMO

OBJECTIVE: The present work demonstrates the optimization of a renilla-based real-time, ultra-bright, non-disruptive, high-throughput bioluminescence assay (HTS) to assess the metabolism of intact Streptococcus mutans biofilms and its utility in screening the antibacterial efficacy of experimental nanofilled dental adhesive resins containing varying concentrations of nitrogen-doped titanium dioxide nanoparticles (N_TiO2). METHODS: Optimization of the assay was achieved by screening real-time bioluminescence changes in intact Streptococcus mutans biofilms imposed by the various experimental biofilm growth parameters investigated (bacterial strain, growth media, sucrose concentration, dilution factor, and inoculum volume). The optimized assay was then used to characterize the antibacterial efficacy of experimental nanofilled dental adhesive resins. The assay's ability to discriminate between bacteriostatic and bactericidal approaches was also investigated. RESULTS: Relative Light Units (RLU) values from the HTS optimization were analyzed by multivariate ANOVA (α = 0.05) and coefficients of variation. An optimized HTS bioluminescence assay was developed displaying RLUs values (brightness) that are much more intense when comparing to other previously reported bioluminescence assays, thereby decreasing the error associated with bioluminescence assays and displaying better utility while investigating the functionalities of antimicrobial nanofilled experimental dental adhesive resins with proven long-term properties. SIGNIFICANCE: The present study is anticipated to positively impact subsequent research on dental materials and oral microbiology because it serves as a valuable screening tool in metabolic-based assays with increased sensitivity and robustness. The assay reported is anticipated to be further optimized to be used as a co-reporter for other Luc based assays.


Assuntos
Antibacterianos , Biofilmes , Ensaios de Triagem em Larga Escala , Medições Luminescentes , Streptococcus mutans , Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Titânio/química , Luciferases , Nanopartículas , Testes de Sensibilidade Microbiana
19.
Sci Rep ; 14(1): 13238, 2024 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853171

RESUMO

The European brittle star Amphiura filiformis emits blue light, via a Renilla-like luciferase, which depends on the dietary acquisition of coelenterazine. Questions remain regarding luciferin availability across seasons and the persistence of luminous capabilities after a single boost of coelenterazine. To date, no study has explored the seasonal, long-term monitoring of these luminous capabilities or the tracking of luciferase expression in photogenic tissues. Through multidisciplinary analysis, we demonstrate that luminous capabilities evolve according to the exogenous acquisition of coelenterazine throughout adult life. Moreover, no coelenterazine storage forms are detected within the arms tissues. Luciferase expression persists throughout the seasons, and coelenterazine's presence in the brittle star diet is the only limiting factor for the bioluminescent reaction. No seasonal variation is observed, involving a continuous presence of prey containing coelenterazine. The ultrastructure description provides a morphological context to investigate the green autofluorescence signal attributed to coelenterazine during luciferin acquisition. Finally, histological analyses support the hypothesis of a pigmented sheath leading light to the tip of the spine. These insights improve our understanding of the bioluminescence phenomenon in this burrowing brittle star.


Assuntos
Pirazinas , Estações do Ano , Animais , Pirazinas/metabolismo , Imidazóis , Equinodermos , Luminescência , Luciferases/metabolismo , Luciferases/genética , Medições Luminescentes/métodos , Luz
20.
J Vis Exp ; (207)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38884479

RESUMO

To control and decrease the public health impact of human protozoan diseases such as Chagas disease, leishmaniasis, and human African trypanosomiasis, expediting the development of new drugs and vaccines is necessary. However, this process is filled with difficulties such as highly complex parasite biology and disease pathogenesis and, as typical for neglected tropical diseases, comparatively limited funding for research and development. Thus, in vitro and in vivo study models that can sufficiently reproduce infection and disease key features while providing rational use of resources are essential for progressing research for these conditions. One example is the in vivo bioluminescence imaging (BLI) mouse model for Chagas disease, which provides highly sensitive detection of long wavelength light generated by Trypanosoma cruzi parasites expressing luciferase. Despite this technique becoming the standard approach for drug efficacy in vivo studies, research groups might still struggle to implement it due to a lack of proper practical training on equipment handling and application of quality control procedures, even when suitable BLI equipment is readily available. Considering this scenario, this protocol aims to guide from planning experiments to data acquisition and analysis, with details that facilitate the implementation of protocols in research groups with little or no experience with BLI, either for Chagas disease or for other infectious disease mouse models.


Assuntos
Doença de Chagas , Modelos Animais de Doenças , Medições Luminescentes , Trypanosoma cruzi , Animais , Doença de Chagas/diagnóstico por imagem , Camundongos , Medições Luminescentes/métodos , Trypanosoma cruzi/efeitos dos fármacos , Luciferases/genética , Luciferases/metabolismo , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
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