A5025482937- CRISPR and Genetic Engineering
- DNA Repair Mechanisms
- Sirtuins and Resveratrol in Medicine
- PARP inhibition in cancer therapy
- Erythrocyte Function and Pathophysiology
- Immune Cell Function and Interaction
- Carcinogens and Genotoxicity Assessment
- Molecular Biology Techniques and Applications
- T-cell and B-cell Immunology
- Hormonal Regulation and Hypertension
- Antibiotic Resistance in Bacteria
- Cancer Genomics and Diagnostics
- Antimicrobial Resistance in Staphylococcus
- Bacterial Identification and Susceptibility Testing
- Estrogen and related hormone effects
- Toxin Mechanisms and Immunotoxins
- Advanced biosensing and bioanalysis techniques
- Trypanosoma species research and implications
- Enterobacteriaceae and Cronobacter Research
- Genetics, Aging, and Longevity in Model Organisms
- Blood groups and transfusion
- Single-cell and spatial transcriptomics
- Insect Resistance and Genetics
- Autophagy in Disease and Therapy
- Bacterial biofilms and quorum sensing
National Center for Toxicological Research
2015-2024
United States Food and Drug Administration
2014-2024
National Institute of Environmental Health Sciences
2009-2013
National Institutes of Health
2009-2013
Washington University in St. Louis
2004-2007
Recent studies have revealed new roles for NAD and its derivatives in transcriptional regulation. The evolutionarily conserved Sir2 protein family requires deacetylase activity regulates a variety of biological processes, such as stress response, differentiation, metabolism, aging. Despite absolute requirement NAD, the regulation function by biosynthesis pathways is poorly understood mammals. In this study, we determined kinetics mediated nicotinamide phosphoribosyltransferase (Nampt)...
Abstract DNA base editors have enabled genome editing without generating double strand breaks. The applications of this technology been reported in a variety animal and plant systems, however, their specificity human stem cells has not studied by unbiased genome-wide analysis. Here we investigate the fidelity cytidine deaminase-mediated induced pluripotent (iPSCs) whole sequencing after sustained or transient editor expression. While base-edited iPSC clones significant off-target...
Human liver-derived metabolically competent HepaRG cells have been successfully employed in both two-dimensional (2D) and 3D spheroid formats for performing the comet assay micronucleus (MN) assay. In present study, we investigated expanding genotoxicity endpoints evaluated by detecting mutagenesis using two error-corrected next generation sequencing (ecNGS) technologies, Duplex Sequencing (DS) High-Fidelity (HiFi) Sequencing. Both 2D spheroids were exposed 72 h to N-nitrosodimethylamine...
G protein-coupled receptors (GPCRs) compose the largest family of cell surface and are most common target therapeutic drugs. The nonvisual arrestins, β-arrestin-1 β-arrestin-2, multifunctional scaffolding proteins that play critical roles in GPCR signaling. On binding activated GPCRs at plasma membrane, β-arrestins terminate protein-dependent responses (desensitization) stimulate β-arrestin–dependent signaling pathways. Alterations cellular complement β-arrestin-2 occur many human diseases,...
A transcription factor that regulates developmental events also suppresses transcriptional responses to stress in adult organisms.
Abstract Molnupiravir (MOV) is used to treat COVID‐19. In cells, MOV converted the ribonucleoside analog N4‐hydroxycytidine (NHC) and incorporated into SARS‐CoV‐2 RNA genome during its replication, resulting in mutations. The widespread accumulation of such mutations inhibits propagation. Although safety assessments by many regulatory agencies across world have concluded that genotoxic risks associated with clinical use are low, concerns remain it could induce DNA patients, particularly...
The Pig-a assay is used for monitoring somatic cell mutation in laboratory animals and humans. detects haematopoietic cells deficient glycosylphosphatidylinositol (GPI)-anchored protein surface markers using flow cytometry. However, given that synthesis of the (and expression their genes) independent X-linked gene function its enzyme product, deficiency at may be caused by a number events (e.g. or epigenetic silencing marker itself any about two dozen autosomal genes involved GPI). Here we...
A major question concerning the scientific and regulatory acceptance of rodent red blood cell‐based Pig‐a gene mutation assay is extent to which mutants identified by their phenotype in are caused mutations gene. In this study, we T‐lymphocytes deficient for glycosylphosphatidylinositol‐anchored surface marker, CD48, control 7,12‐dimethylbenz[ a ]anthracene (DMBA)‐treated rats using flow cytometric determined spectra endogenous these cells. CD48‐deficient T‐cells were seeded sorting at one...
Procarbazine is a primary component of antineoplastic combination chemotherapy often used for the treatment Hodgkin's lymphoma. It believed that cytostatic and cytotoxic properties procarbazine are mediated via its interaction with genomic DNA. carcinogen in animal models; it classified as Group 2A compound by IARC. Also known an vitro vivo mutagen genotoxicant. However, molecular mechanism which induces mutations not thoroughly understood spectrum procarbazine-induced described...
Lack of cell surface glycosylphosphatidylinositol (GPI)‐anchored protein(s) has been used as a reporter Pig‐a gene mutation in several model systems. As an extension this work, our laboratory initiated development vitro assay based on the flow cytometric assessment CD90.2 expression mouse lymphoma line L5178Y/ Tk +/− . Cells were exposed to mutagenic and nonmutagenic compounds for 24 hr followed by washout incubation additional 7 days. Following mutant manifestation time, cells labeled with...
The X‐linked Pig‐a gene encodes an enzyme required for the biosynthesis of glycosyl phosphatidylinositol (GPI) anchors. mutant cells fail to synthesize GPI and express GPI‐anchored protein markers (e.g., CD90) on their surface. Marker deficiency serves as a phenotypic indicator mutation in various vivo assays. Here, we describe vitro assay L5178Y Tk +/– mouse lymphoma cells, which mutant‐phenotype are measured by flow cytometry using fluorescent anti‐CD90 antibody. Increased frequencies...
Identification of mutations induced by xenotoxins is a common task in the field genetic toxicology. Mutations are often detected clonally expanding potential mutant cells and genotyping each viable clone Sanger sequencing. Such “clone‐by‐clone” approach requires significant time effort, sometimes even impossible to implement. Alternative techniques for efficient mutation identification would greatly benefit both basic regulatory toxicology research. Here, we report development Mutation...
We analyzed antimicrobial resistance and virulence traits in multidrug-resistant (MDR) E. coli isolates obtained from imported shrimp using whole-genome sequences (WGSs). Antibiotic profiles were determined phenotypically. WGSs identified key characteristics, including their multilocus sequence type (MLST), serotype, factors, antibiotic genes, mobile elements. Most of the exhibited to gentamicin, streptomycin, ampicillin, chloramphenicol, nalidixic acid, ciprofloxacin, tetracycline,...
Genetic toxicology uses several assays to identity mutagens and protects the public. Most of these assays, however, rely on reporter genes, can only measure mutation indirectly based phenotype, often require specific cell lines or animal models-features that impede their integration with existing emerging toxicological models, such as organoids. In this study, we show PacBio Single-Molecule, Real-Time (PB SMRT) sequencing identified substitution mutations caused by chemical in Escherichia...
Abstract Many conventional genetic toxicology assays require specialized cell cultures or animals and can only detect mutations that inactivate the function of a reporter gene. These limitations make such incompatible with many toxicological models but could be overcome by development techniques capable directly detecting genome‐wide somatic through DNA sequencing. PacBio sequencing generate almost error‐free consensus reads repeatedly inspecting both strands from circularized molecules (a...