Ecological genetics

BACKGROUND: The water frog (Pelophylax esculentus complex) is hybrid in composition. In view of the fact that a large number of data on the species composition of the water frog and very scarce material on the genetic structure of populations are available in the literature, we aimed to analyze the genetic structure of populations of the water frog in the southern part of the Middle Russian upland, which was one of the refugia for many species during the glacial epoch and the center of dispersion in the postglacial time, based on DNA microsatellite markers.

MATERIALS AND METHODS: The study involved 36 local populations. DNA variability was analyzed by multiplex SSR-PCR. Seven loci (Res 14, Res 15, Res 17, Res 22, Rrid059A, Rrid082A, and Rrid171A) were used for amplification. Fragment analysis of PCR products was performed on an ABI PRISM 3500 automated capillary DNA sequencer (Applied Biosystems, USA).

RESULTS: The total number of alleles detected ranged from 13 to 41. The effective number of alleles (A_e) averaged 4.569 ± 0.219, the Chenon index (I) 1.567 ± 0.04, level of expected heterozygosity (Н_е) 0.68 ± 0.01. According to Wright’s model, the greatest contribution to genetic variability is made by the heterogeneity of individuals within populations, some of which are of a hybrid nature (F_is = 0.281 ± 0.069, F_it = 0.413 ± 0.053, F_st = 0.180 ± 0.017). The average indicator of the intensity of gene exchange between populations (N_m) was 1.212 ± 0.142 individuals per generation. The calculation of the effective abundance using the LD method indicates a high level of viability of the studied groups of the frogs.

CONCLUSION: The results demonstrated a high level of genetic diversity and viability of most of the studied groups, which, due to the intense gene exchange between them, can represent a single panmictic population. The data of the genetic analysis support the active adaptation of P. esculentus complex to living in an urbanized environment.

BACKGROUND: Garden pea (Pisum sativum L.) possesses the ability to form beneficial symbioses with various soil microorganisms. However, different pea cultivars, genotypes, and lines gain more or less benefit from these interactions, so the trait named “efficiency of interaction with soil microorganisms” (EIBSM) was suggested to describe this phenomenon. The molecular mechanisms underlying the manifestation of the EIBSM trait are not properly studied, and only few works focusing on plant responses to combined microbial preparations have been published to date.

METHODS: Eight pea lines previously described as contrasting in manifestation of the EIBSM trait were grown in pots with soil under combined inoculation with nodule bacteria and arbuscular mycorrhizal fungi, and the transcriptome profiles of the whole root systems of the plants were investigated using 3'MACE RNA sequencing.

RESULTS: The relatedness of the lines inferred from the analysis of transcripts’ SNVs (Single Nucleotide Variants) corresponded to the manifestation of the EIBSM trait: three high-EIBSM lines and three low-EIBSM lines formed two distinct clusters. Thus, the gene expression profiles were compared between these two clusters, which enabled identification of transcriptome signatures characteristic for each group. The lines previously described as high-EIBSM have lower symbiotic activity, and the expression levels of pathogen response genes were elevated compared to the lines with low EIBSM.

CONCLUSION: This result suggests that the mechanism of high interaction efficiency may be connected to stricter host control of symbionts, allowing such plants to expend less on the symbioses.

This paper considers studies aimed at identifying markers of genotoxicity (chromosomal aberrations, micronuclei, and DNA damage assessed by the DNA comet assay) in patients with both gestational diabetes mellitus (GDM) and diabetes type 1 and 2 (T1DM and T2DM, respectively), as well as possible changes in the levels of these genotoxic markers under the influence of medicines and nutritions. Patients with T2DM are characterized by an increased level of genotoxicity markers. The results of genotoxicity markers in patients with T1DM and GDM studies are contradictory, however, they indicate the presence of an increased genotoxic load rather than its absence. The levels of genotoxic damage in diabetic patients may be reduced by physical exercises, diet, and/or hypoglycemic drugs. Metformin, Afobazole and Noopept are recommended for experimental and clinical studies as possible drug candidates that reduce the levels of genotoxic biomarkers in diabetic patients.

Ambiguity of genetic terms usage leads to their misinterpretation and learning difficulties. The content of some concepts is analyzed as well as haziness and mistakes in usage of corresponding terms such as gene, allele, genotype, phenotype, polymorphism, heritability, variability and few others. Limitations of the model dividing separately impact of the environment and genotype in a feature formation are explored. The interaction of the environment and hereditary material is suggested as basic factor of genetic and phonetic variability.