Quantitative genomic mapping of DNA damage may provide insights into the underlying mechanisms of damage and repair. Sequencing based approaches are bound to the limitations of PCR amplification bias and read length which hamper both the accurate quantitation of damage events and the ability to map them to structurally complex genomic regions. Optical Genome mapping in arrays of parallel nanochannels allows physical extension and genetic profiling of millions of long genomic DNA fragments, and has matured to clinical utility for characterization of complex structural aberrations in cancer genomes. Here we present a new mapping modality, Repair-Assisted Damage Detection - Optical Genome Mapping (RADD-OGM), a method for single-molecule level mapping of DNA damage on a genome-wide scale. Leveraging ultra-long reads to assemble the complex structure of a sarcoma cell-line genome, we mapped the genomic distribution of oxidative DNA damage, identifying regions more susceptible to DNA oxidation. We also investigated DNA repair by allowing cells to repair chemically induced DNA damage, pinpointing locations of concentrated repair activity, and highlighting variations in repair efficiency. Our results showcase the potential of the method for toxicogenomic studies, mapping the effect of DNA damaging agents such as drugs and radiation, as well as following specific DNA repair pathways by selective induction of DNA damage. The facile integration with optical genome mapping enables performing such analyses even in highly rearranged genomes such as those common in many cancers, a challenging task for sequencing-based approaches.

• Klíčová slova
• CNV, Cancer genomes, Cytogenetics, DNA damage, DNA repair, Long-reads, Nanochannels, OGM, Osteosarcoma, Oxidative damage, RADD, S.V., Single molecule, Toxicogenomics,
• MeSH
• bromičnany toxicita   MeSH
• lidé MeSH
• mapování chromozomů * přístrojové vybavení   metody   MeSH
• mikrofluidní analytické techniky * přístrojové vybavení   metody   MeSH
• nádorové buněčné linie MeSH
• nanotechnologie * přístrojové vybavení   metody   MeSH
• oprava DNA genetika   MeSH
• oxidační stres účinky léků   genetika   MeSH
• poškození DNA * genetika   MeSH
• regulace genové exprese MeSH
• stanovení celkové genové exprese MeSH
• toxikogenetika * přístrojové vybavení   metody   MeSH
• variabilita počtu kopií segmentů DNA MeSH
• zobrazení jednotlivé molekuly * přístrojové vybavení   metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bromičnany MeSH
• potassium bromate MeSH Prohlížeč

In this review, we present an overview of transcriptomic responses to chemical exposures in a variety of fish species. We have discussed the use of several molecular approaches such as northern blotting, differential display reverse transcription-polymerase chain reaction (DDRT-PCR), suppression subtractive hybridization (SSH), real time quantitative PCR (RT-qPCR), microarrays, and next-generation sequencing (NGS) for measuring gene expression. These techniques have been mainly used to measure the toxic effects of single compounds or simple mixtures in laboratory conditions. In addition, only few studies have been conducted to examine the biological significance of differentially expressed gene sets following chemical exposure. Therefore, future studies should focus more under field conditions using a multidisciplinary approach (genomics, proteomics and metabolomics) to understand the synergetic effects of multiple environmental stressors and to determine the functional significance of differentially expressed genes. Nevertheless, recent developments in NGS technologies and decreasing costs of sequencing holds the promise to uncover the complexity of anthropogenic impacts and biological effects in wild fish populations.

• Klíčová slova
• Aquatic toxicology, Ecotoxicology, Environmental monitoring, Pollution, Toxicants, Toxicogenomics,
• MeSH
• chemické látky znečišťující vodu toxicita   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• ryby genetika   MeSH
• stanovení celkové genové exprese * MeSH
• subtraktivní hybridizace MeSH
• toxikologie metody   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH

This study used toxicogenomics to identify the complex biological response of human lung BEAS-2B cells treated with organic components of particulate matter in the exhaust of a diesel engine. First, we characterized particles from standard diesel (B0), biodiesel (methylesters of rapeseed oil) in its neat form (B100) and 30% by volume blend with diesel fuel (B30), and neat hydrotreated vegetable oil (NEXBTL100). The concentration of polycyclic aromatic hydrocarbons (PAHs) and their derivatives in organic extracts was the lowest for NEXBTL100 and higher for biodiesel. We further analyzed global gene expression changes in BEAS-2B cells following 4 h and 24 h treatment with extracts. The concentrations of 50 µg extract/mL induced a similar molecular response. The common processes induced after 4 h treatment included antioxidant defense, metabolism of xenobiotics and lipids, suppression of pro-apoptotic stimuli, or induction of plasminogen activating cascade; 24 h treatment affected fewer processes, particularly those involved in detoxification of xenobiotics, including PAHs. The majority of distinctively deregulated genes detected after both 4 h and 24 h treatment were induced by NEXBTL100; the deregulated genes included, e.g., those involved in antioxidant defense and cell cycle regulation and proliferation. B100 extract, with the highest PAH concentrations, additionally affected several cell cycle regulatory genes and p38 signaling.

• Klíčová slova
• alternative fuels, diesel, diesel exhaust particles, gene expression profiles, organic extracts,
• MeSH
• anotace sekvence MeSH
• benzin analýza   toxicita   MeSH
• biopaliva analýza   toxicita   MeSH
• bronchy cytologie   účinky léků   metabolismus   MeSH
• epitelové buňky cytologie   účinky léků   metabolismus   MeSH
• látky znečišťující vzduch analýza   toxicita   MeSH
• lidé MeSH
• oleje rostlin chemie   MeSH
• pevné částice analýza   toxicita   MeSH
• polycyklické aromatické uhlovodíky analýza   toxicita   MeSH
• regulace genové exprese u rostlin * MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• signální transdukce MeSH
• stanovení celkové genové exprese MeSH
• transformované buněčné linie MeSH
• výfukové emise vozidel analýza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• benzin MeSH
• biopaliva MeSH
• látky znečišťující vzduch MeSH
• oleje rostlin MeSH
• pevné částice MeSH
• polycyklické aromatické uhlovodíky MeSH
• rostlinné proteiny MeSH
• výfukové emise vozidel MeSH

Omics-based methods are increasingly used in current ecotoxicology. Therefore, a large number of observations for various toxic substances and organisms are available and may be used for identifying modes of action, adverse outcome pathways, or novel biomarkers. For these purposes, good statistical analysis of toxicogenomic data is vital. In contrast to established ecotoxicological techniques, concentration-response modeling is rarely used for large datasets. Instead, statistical hypothesis testing is prevalent, which provides only a limited scope for inference. The present study therefore applied automated concentration-response modeling for 3 different ecotoxicotranscriptomic and ecotoxicometabolomic datasets. The modeling process was performed by simultaneously applying 9 different regression models, representing distinct mechanistic, toxicological, and statistical ideas that result in different curve shapes. The best-fitting models were selected by using Akaike's information criterion. The linear and exponential models represented the best data description for more than 50% of responses. Models generating U-shaped curves were frequently selected for transcriptomic signals (30%), and sigmoid models were identified as best fit for many metabolomic signals (21%). Thus, selecting the models from an array of different types seems appropriate, because concentration-response functions may vary because of the observed response type, and they also depend on the compound, the organism, and the investigated concentration and exposure duration range. The application of concentration-response models can help to further tap the potential of omics data and is a necessary step for quantitative mixture effect assessment at the molecular response level.

• Klíčová slova
• Biostatistics, Dose-response modeling, Ecotoxicogenomics, Mixture toxicity, Myriophyllum, Zebrafish embryo,
• MeSH
• dánio pruhované růst a vývoj   metabolismus   MeSH
• ekosystém * MeSH
• embryo nesavčí účinky léků   metabolismus   MeSH
• genomika * MeSH
• látky znečišťující životní prostředí toxicita   MeSH
• lineární modely MeSH
• metabolomika * MeSH
• rychlé screeningové testy MeSH
• sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
• tetrachlorethylen toxicita   MeSH
• transkriptom účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• látky znečišťující životní prostředí MeSH
• tetrachlorethylen MeSH