Interactions of living organisms with their environment mainly involve modulation of gene expression by stimulation or silencing. One of the epigenetic mechanisms that regulate translation and the levels of transcripts is RNA interference, in which microRNAs (miRNAs) address RNA-induced silencing complexes (RISCs) to degrade specific mRNAs or to silence their translation. In this mechanism, double stranded RNA structure is crucial for miRNA biogenesis and the action of RISCs. RNA molecules can be modified structurally by reactive oxygen and nitrogen species (ROS and RNS) that are produced in cells of all aerobic organisms and may be induced by environmental factors. Here we describe experiments in which changes of ROS and transcript levels are induced by X-irradiation and measured using flow cytometer and the fluorescent dye 2',7'-dichlorofluorescein diacetate and microarray methods in cultured human K562, Me45 and HCT116 cells. Analysis of the nucleotide sequences of mRNAs which are up- or down-regulated after irradiation shows significant differences in the distributions of miRNA-targeted motives between these two groups. Immediately after irradiation most miRNAs behave as "up-regulators", showing more targets in up-than in down-regulated transcripts, and this changes about 12h later when we also observe changes in ROS and miRNA levels. Our results suggest that the changes in the transcriptome could result from changes in RNA interference and that these effects could be related to the changed ROS levels in irradiated cells. We propose that such modulation of gene expression at the mRNA level may be implicated more generally in cellular responses to stresses where ROS levels change.
Human mesenchymal stromal cells (MSCs) are attractive for both medical practice and biomedical research. Nonfreezing short-term storage may provide safe and simple transportation and promote the practical use of MSCs. We aimed to determine the duration of efficient storage at ambient temperature (22°C) of human dermal MSCs in different three-dimensional organization and to investigate the role of cell metabolic mode in the resistance to the ambient storage damaging factors.
Key Laboratory of Plant Nutrition and the Agro-Environment in Northwest China, Ministry of Agriculture and Rural Affairs, College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi 712100, China.
Microplastics (MPs) have been confirmed as a hotspot for antibiotic resistance genes (ARGs) in wastewater. However, the impact of MPs on the transfer of ARGs in wastewater treatment remains unclear. This study investigated the roles and mechanisms of conventional (polystyrene, PS) and biodegradable (polylactic acid, PLA) MPs in the conjugative transfer of ARGs during ultraviolet disinfection.
Sperm cryopreservation is a useful storage technique in artificial insemination. Nanoparticles and nanovesicles such as exosomes are widely used in sperm cryopreservation procedures to alleviate cold-induced injury inflicted during sperm freezing. The objective of the present study was to examine the impact of varying concentrations of exosomes derived from seminal plasma added to a freezing extender on the quality of post-thawed bull sperm.
Background And Objectives: Friedreich's Ataxia (FRDA) is a genetic disease that affects a variety of different tissues. The disease is caused by a mutation in the gene ( which is important for the synthesis of iron-sulfur clusters. The primary pathologies of FRDA are loss of motor control and cardiomyopathy.
As many proteins prioritize functionality over constancy of structure, a proteome is the shortest stave in the Liebig's barrel of cell sustainability. In this regard, both prokaryotes and eukaryotes possess abundant machinery supporting the quality of the proteome in healthy and stressful conditions. This machinery, namely chaperones, assists in folding, refolding, and the utilization of client proteins.
