Alternative oxidase affects ascorbate metabolism in plants under high-light conditions: possible links between respiratory electron transport pathways in mitochondria.

Some aspects of the relationship between ascorbate (Asc) metabolism and the functioning of mitochondrial alternative oxidase (AOX) under moderately high light (MHL, 400 μmol m s) using mutant lines were studied. After 8 h of MHL in the antisense line (AS-12), decreasing the relative reduced Asc pool due to increased ascorbate peroxidase activity was accompanied by the accumulation of a pool of the other highly effective antioxidant - glutathione. In the vitamin C-deficient line (), expression and the Asc pool were expectedly low, and after 8 h of MHL, dehydroascorbate (DHA) content was increased, although slight activation of AOX and L-galacton-1,4-lactone dehydrogenase was detected.

Soil Microbiome in Conditions of Oil Pollution of Subarctic Ecosystems.

The present study aimed to investigate the recovery of soil quality and the bacterial and fungal communities following various recultivation methods in areas contaminated with oil. Oil spills are known to have severe impacts on ecosystems; thus, the restoration of contaminated soils has become a significant challenge nowadays. The study was conducted in the forest-tundra zone of the European North-East, where 39 soil samples from five oil-contaminated sites and reference sites were subjected to metagenomic analyses.

Dose-Dependent Effect of Mitochondrial Superoxide Dismutase Gene Overexpression on Radioresistance of HEK293T Cells.

Over the last two decades, a multitude of gain-of-function studies have been conducted on genes that encode antioxidative enzymes, including one of the key enzymes, manganese superoxide dismutase (). The results of such studies are often contradictory, as they strongly depend on many factors, such as the gene overexpression level. In this study, the effect of altering the ectopic expression level of major transcript variants of the gene on the radioresistance of HEK293T cells was investigated using CRISPRa technology.

Effects of Antioxidant Gene Overexpression on Stress Resistance and Malignization In Vitro and In Vivo: A Review.

Reactive oxygen species (ROS) are normal products of a number of biochemical reactions and are important signaling molecules. However, at the same time, they are toxic to cells and have to be strictly regulated by their antioxidant systems. The etiology and pathogenesis of many diseases are associated with increased ROS levels, and many external stress factors directly or indirectly cause oxidative stress in cells.

Expression in Affects the State of Chloroplast Photoprotective Systems under Moderately High Light Conditions.

Alternative oxidase (AOX) in the mitochondrial electron transport chain is considered important for sustaining photosynthesis under high light conditions. Here, we examined the effects of the AOX pathway on the state of chloroplast photoprotective systems. plants (4 weeks old), comprising three genotypes (wild type [WT], overexpressing [XX-2] and antisense [AS-12] lines for ), were exposed to moderately high light conditions (MHL, 400 μmol m s) in a short-term experiment (8 h).

Responses of genes of DNA repair, alternative oxidase, and pro-/antioxidant state in with altered expression of to gamma irradiation.

Purpose: High doses of gamma (γ) irradiation cause oxidative stress and DNA damage. Alternative oxidase (AOX) catalyzes the energy-dissipating cyanide-resistant alternative pathway in plant mitochondria and is an important part of the cellular defense network under stress conditions. In this study, plants with an altered expression of the gene were exposed by high dose-rate ionizing radiation to assess the expression of genes of DNA repair and pro-/antioxidant states to elucidate the functional significance of AOX in plant stress response.

The gene expression profiles of mitochondrial respiratory components in Arabidopsis plants with differing amounts of under high intensity light.

We compared the expression of mitochondrial alternative oxidase (AOX) and other non-phosphorylating respiratory components (NPhPs) in wild type and transgenic following short-term transfer of plants to higher irradiance conditions to gain more insight into the mechanisms of AOX functioning under light. The overexpressing line (XX-2) showed the highest amount of transcripts and AOX1A synthesis during the entire experiment, and many NPhPs genes were down-regulated after 6-8 h under the higher light conditions. Antisense AS-12 plants displayed a compensatory effect, typically after 8 h of exposure to higher irradiance, by up-regulating their expression of the majority of genes encoding AOX and other respiratory components.

Radioresistance, DNA Damage and DNA Repair in Cells With Moderate Overexpression of RPA1.

Molecular responses to genotoxic stress, such as ionizing radiation, are intricately complex and involve hundreds of genes. Whether targeted overexpression of an endogenous gene can enhance resistance to ionizing radiation remains to be explored. In the present study we take an advantage of the CRISPR/dCas9 technology to moderately overexpress the gene that encodes a key functional subunit of the replication protein A (RPA).

Genetic analysis in earthworm population from area contaminated with radionuclides and heavy metals.

This study assessed the effects of environmental contamination by naturally occurring radionuclides and heavy metals on the genetic structure of a population of the earthworm Aporrectodea caliginosa. A. caliginosa were collected from four sites and characterized by amplified fragment length polymorphism (AFLP) analyses.

Recent Trends in Enhancing the Resistance of Cultivated Plants to Heavy Metal Stress by Transgenesis and Transcriptional Programming.

Normal growth and development of high plants strongly depends on the concentration of microelements, including essential heavy metals, in the substrate. However, an excess of those elements may become harmful. Therefore, micronutrient concentrations in plant tissue should be well-balanced and controlled by homeostatic mechanisms.

Microsatellite polymorphism of Trifolium pratense population at the conditions of radioactive and chemical contamination of soil (Komi republic, Russia).

There is no clear understanding of microevolutionary changes in natural populations of plants and animals due to anthropogenic contamination of the environment with toxicants and mutagens. But such data are necessary to forecast long-term effects of human activity. In this research, we studied genetic polymorphism in T.

Differential Molecular Stress Responses to Low Compared to High Doses of Ionizing Radiation in Normal Human Fibroblasts.

Understanding the mechanisms producing low dose ionizing radiation specific biological effects represents one of the major challenges of radiation biology. Although experimental evidence does suggest that various molecular stress response pathways may be involved in the production of low dose effects, much of the detail of those mechanisms remains elusive. We hypothesized that the regulation of various stress response pathways upon irradiation may differ from one another in complex dose-response manners, causing the specific and subtle low dose radiation effects.

Effects on non-human species inhabiting areas with enhanced level of natural radioactivity in the north of Russia: a review.

Results of long-term radioecological investigations in areas with an enhanced level of natural radioactivity in the north of Russia are summarized. Deleterious changes within animal and plant populations inhabiting areas with an enhanced level of natural radioactivity in the Komi Republic were revealed. These changes are expressed in enhanced levels of mutagenesis, destructive processes in the tissues of animals, disturbances of reproductive functions and reduced offspring viability.