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Navratil, V.

Publications and source records attributed to Navratil, V..

3 recordsLinked to original sources

Transposable element activity in the transcriptomic analysis of mouse pancreatic tumors

Transposable elements (TEs) are middle-repeated DNA sequences that can move along chromosomes using internal coding and regulatory regions. By their ability to move and because they are repeated, TEs can promote mutations. Especially they can alter the expression pattern of neighboring genes and have been shown to be involved in the mammalian regulatory network evolution. Human and mouse share more than 95% of their genomes and are affected by comparable diseases, which makes the mouse a perfect model in cancer research. However not much investigation concerning the mouse TE content has been made on this topics. In human cancer condition, a global activation of TEs can been observed which may ask the question of their impact on neighboring gene functioning. In this work, we used RNA sequences of highly aggressive pancreatic tumors from mouse to analyze the gene and TE deregulation happening in this condition compared to pancreas from healthy animals. Our results show that several TE families are deregulated and that the presence of TEs is associated with the expression divergence of genes in the tumor condition. These results illustrate the potential role of TEs in the global deregulation at work in the cancer cells.

genomics

Large-scale deregulation of gene expression by artificial light at night in tadpoles of common toads

Artificial light at night (ALAN) affects numerous physiological and behavioural mechanisms in various species by potentially disturbing circadian timekeeping systems. Although gene-specific approaches have already shown the deleterious effect of ALAN on the circadian clock, immunity and reproduction, large-scale transcriptomic approaches with ecologically relevant light levels are still lacking to assess the global impact of ALAN on biological processes. Moreover, studies have focused mainly on variations in gene expression during the night in the presence of ALAN but never during the day. In a controlled laboratory experiment, transcriptome sequencing of Bufo bufo tadpoles revealed that ALAN affected gene expression at both night and daytime with a dose-dependent effect and globally induced a downregulation of genes. ALAN effects were detected at very low levels of illuminance (0.1 lux) and affected mainly genes related to the innate immune system and, to a lesser extend to lipid metabolism. These results indicate that a broad range of physiological pathways is impacted at the molecular level by very low levels of ALAN potentially resulting in reduced survival under environmental immune challenges.

ecology