Metals and metalloids pollution levels, partitioning, and sources in the environmental compartments of a small urban catchment in Moscow megacity.

This study examines the contamination levels and sources of 32 metals and metalloids (MMs) in environmental compartments (roadside soil, road dust, and river suspended sediments) of a small urbanized river catchment located in Moscow megacity. MMs partitioning between particle size fractions (PM, PM, and PM) was analyzed by ICP-MS and ICP-AES methods. The pollution level of particle size fractions with MMs decreases in the following series: road dust > suspended sediments > soils.

Wide-scale identification of novel/eliminated genes responsible for evolutionary transformations.

Background: It is generally accepted that most evolutionary transformations at the phenotype level are associated either with rearrangements of genomic regulatory elements, which control the activity of gene networks, or with changes in the amino acid contents of proteins. Recently, evidence has accumulated that significant evolutionary transformations could also be associated with the loss/emergence of whole genes. The targeted identification of such genes is a challenging problem for both bioinformatics and evo-devo research.

Potential Role of AGR2 for Mammalian Skin Wound Healing.

The limited ability of mammals to regenerate has garnered significant attention, particularly in regard to skin wound healing (WH), which is a critical step for regeneration. In human adults, skin WH results in the formation of scars following injury or trauma, regardless of severity. This differs significantly from the scarless WH observed in the fetal skin of mammals or anamniotes.

Anthropogenic factors affecting the Moskva River water quality: levels and sources of nutrients and potentially toxic elements in Moscow metropolitan area.

This study aims to identify the main patterns of distribution and sources of pollutants in the Moskva River and their influence on river water quality under different levels of anthropogenic stress caused by the largest megacity in Europe - Moscow. For this study, we determined concentrations of 18 trace elements, nutrient elements and major ions, chemical and biochemical oxygen demand, and physical parameters of water at 45 stations on the Moskva River and 20 stations on its tributaries during spring flood and low water of 2019 and 2020 to identify the extent and mechanisms of urban impact on its water chemistry. Chemical elements concentrations have been determined using ICP-MS and ICP-AES methods.

The Secreted Protein Disulfide Isomerase Ag1 Lost by Ancestors of Poorly Regenerating Vertebrates Is Required for Tail Regeneration.

Warm-blooded vertebrates regenerate lost limbs and their parts in general much worse than fishes and amphibians. We previously hypothesized that this reduction in regenerative capability could be explained in part by the loss of some genes important for the regeneration in ancestors of warm-blooded vertebrates. One of such genes could be , which encodes secreted protein disulfide isomerase of the Agr family.

Bioinformatics Screening of Genes Specific for Well-Regenerating Vertebrates Reveals c-answer, a Regulator of Brain Development and Regeneration.

The molecular basis of higher regenerative capacity of cold-blooded animals comparing to warm-blooded ones is poorly understood. Although this difference in regenerative capacities is commonly thought to be a result of restructuring of the same regulatory gene network, we hypothesized that it may be due to loss of some genes essential for regeneration. We describe here a bioinformatic method that allowed us to identify such genes.

Agr2-interacting Prod1-like protein Tfp4 from Xenopus laevis is necessary for early forebrain and eye development as well as for the tadpole appendage regeneration.

The Agr family genes, Ag1, Agr2, and Agr3, encode for the thioredoxin domain containing secreted proteins and are specific only for vertebrates. These proteins are attracting increasing attention due to their involvement in many physiological and pathological processes, including exocrine secretion, cancer, regeneration of the body appendages, and the early brain development. At the same time, the mode by which Agrs regulate intracellular processes are poorly understood.

Ras-dva small GTPases lost during evolution of amniotes regulate regeneration in anamniotes.

In contrast to amniotes (reptiles, birds and mammals), anamniotes (fishes and amphibians) can effectively regenerate body appendages such as fins, limbs and tails. Why such a useful capability was progressively lost in amniotes remains unknown. As we have hypothesized recently, one of the reasons for this could be loss of some genes regulating the regeneration in evolution of amniotes.

Expression of and mRNAs and encoded proteins in zebrafish embryos.

In (zebrafish), members of the gene-family (, ) are considered as ventralizing factors. We investigated not only the expression of their mRNAs by hybridization at different stages of embryonic development, but also the spatial distribution of the encoded proteins by whole-mount immunostaining. We showed mRNA to be available in embryos since early cleavage and later on.

The secreted factor Ag1 missing in higher vertebrates regulates fins regeneration in Danio rerio.

Agr family includes three groups of genes, Ag1, Agr2 and Agr3, which encode the thioredoxin domain-containing secreted proteins and have been shown recently to participate in regeneration of the amputated body appendages in amphibians. By contrast, higher vertebrates have only Agr2 and Agr3, but lack Ag1, and have low ability to regenerate the body appendages. Thus, one may hypothesize that loss of Ag1 in evolution could be an important event that led to a decline of the regenerative capacity in higher vertebrates.

Ras-dva1 small GTPase regulates telencephalon development in Xenopus laevis embryos by controlling Fgf8 and Agr signaling at the anterior border of the neural plate.

We previously found that the small GTPase Ras-dva1 is essential for the telencephalic development in Xenopus laevis because Ras-dva1 controls the Fgf8-mediated induction of FoxG1 expression, a key telencephalic regulator. In this report, we show, however, that Ras-dva1 and FoxG1 are expressed in different groups of cells; whereas Ras-dva1 is expressed in the outer layer of the anterior neural fold, FoxG1 and Fgf8 are activated in the inner layer from which the telencephalon is derived. We resolve this paradox by demonstrating that Ras-dva1 is involved in the transduction of Fgf8 signal received by cells in the outer layer, which in turn send a feedback signal that stimulates FoxG1 expression in the inner layer.

Agr genes, missing in amniotes, are involved in the body appendages regeneration in frog tadpoles.

Previous studies have shown that Agr genes, which encode thioredoxin domain-containing secreted proteins, play a critical role in limb regeneration in salamanders. To determine the evolutionary conservation of Agr function, it is important to examine whether Agrs play a similar role in species with a different type of regeneration. Here, we refined the phylogeny of Agrs, revealing three subfamilies: Ag1, Agr2 and Agr3.

Expression patterns of genes encoding small GTPases Ras-dva-1 and Ras-dva-2 in the Xenopus laevis tadpoles.

Small GTPases of the recently discovered Ras-dva family are specific to the Vertebrate phylum. In Xenopus laevis, Ras-dva-1 is expressed during gastrulation and neurulation in the anterior ectoderm where it regulates the early development of the forebrain and cranial placodes (Tereshina et al., 2006).

Hydroxyproline-based DNA mimics provide an efficient gene silencing in vitro and in vivo.

To be effective, antisense molecules should be stable in biological fluids, non-toxic, form stable and specific duplexes with target RNAs and readily penetrate through cell membranes without non-specific effects on cell function. We report herein that negatively charged DNA mimics representing chiral analogues of peptide nucleic acids with a constrained trans-4-hydroxy-N-acetylpyrrolidine-2-phosphonate backbone (pHypNAs) meet these criteria. To demonstrate this, we compared silencing potency of these compounds with that of previously evaluated as efficient gene knockdown molecules hetero-oligomers consisting of alternating phosphono-PNA monomers and PNA-like monomers based on trans-4-hydroxy-L-proline (HypNA-pPNAs).

Ras-dva, a member of novel family of small GTPases, is required for the anterior ectoderm patterning in the Xenopus laevis embryo.

Ras-like small GTPases are involved in the regulation of many processes essential for the specification of the vertebrate body plan. Recently, we identified the gene of novel small GTPase Ras-dva, which is specifically expressed at the anterior margin of the neural plate of the Xenopus laevis embryo. Now, we demonstrate that Ras-dva and its homologs in other species constitute a novel protein family, distinct from the previously known families of small GTPases.