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Belgica antarctica is one of the two native chironomid species of the Antarctic Peninsula. In this species, adult males and females are considerably different, yet the question of larval sex differences in morphometric parameters remains unanswered. In this paper, we analyze five morphometric parameters: head capsule length, head capsule width, mandible width, mandible length, mentum length of 140 fourth-instar larvae of B. antarctica from seven study plots in the south of Petermann Island, Wilhelm Archipelago, Antarctic Peninsula. To infer possible sexual dimorphism, we use the methods of unsupervised analysis (PCA and hierarchical clusterization). Our results suggest that the selected morphometric features of width and length are highly intercorrelated and cannot differentiate sex in the sampled larvae of B. antarctica.

The gene BRCA1 plays a key role in DNA repair in breast and ovarian cell lines and this is considered one of target tumor suppressor genes in same line of cancers. The 5382insC mutation is among the most frequently detected in patients (Eastern Europe) with triple-negative breast cancer (TNBC). In Ukraine, there is not enough awareness of necessity to test patients with TNBC for BRCA1 mutations. That is why this group of patients is not well-studied, even through is known the mutation may affect the course of disease.The biological samples of 408 female patients were analyzed of the 5382insC mutation in BRCA1. We compared the frequency of the 5382insC mutation in BRCA1 gene observed in Ukraine with known frequencies in other countries.For patients with TNBC, BRCA1 mutations frequency was 11.3%, while in patients with luminal types of breast cancers, the frequency was 2.8%. Prevalence of 5382insC among TNBC patients reported in this study was not different from those in Tunisia, Poland, Russia, and Bulgaria, but was higher than in Australia and Germany.The BRCA1 c.5382 mutation rate was recorded for the first time for TNBC patients in a Ukrainian population. The results presented in this study underscore the importance of this genetic testing of mutations in patients with TNBC. Our study supports BRCA1/2 genetic testing for all women diagnosed with TNBC, regardless of the age of onset or family history of cancer and not only for women diagnosed with TNBC at60y.o., as guidelines recommend.

Genome of antarctic endemic Belgica antarctica Jacobs has been sequenced. However, no set of inversion diagnostic markers has ever been assigned for the species. Using the classical method of polytene chromosome squash preparation, we found three heterozygous inversions located on the second (two heterozygous inversions) and third chromosomes (one heterozygous inversion) in the Belgica antarctica population of a cape o f Wiencke Island, 5 00 m to SW from Port Lockroy. The chromosome set and chromosome variability did not differ from those described in the literature (Atchley and Davis 1979). Every salivary gland chromosome ha d its own markers by which it can be determined. However, we did not find a sex-linked inversion on chromosome III and heterozygous inversion on chromosome I, reported in earlier studies . For the first time , we observed a strong heterochromatin band in chromosome III at the telomere of one arm. Our data show not only the stability of the described inversions in the population but also the usefulness of the squash preparation technique in the studies of genetic variability of Belgica antarctica in present time .

Belgica antarctica (Diptera: Chironomidae), a brachypterous midge endemic to the maritime Antarctic, was first described in 1900. Over more than a century of study, a vast amount of information has been compiled on the species (3 750 000 Google search results as of January 10, 2021), encompassing its ecology and biology, life cycle and reproduction, polytene chromosomes, physiology, biochemistry and, increasingly, omics. In 2014, B. antarctica's genome was sequenced, further boosting research. Certain developmental stages can be cultured successfully in the laboratory. Taken together, this wealth of information allows the species to be viewed as a natural model organism for studies of adaptation and function in extreme environments.

Wolbachia is an intracellular symbiont that infects a large number of arthropod species, ensuring its success in populations by influencing host reproduction. The wMel strain in Drosophila melanogaster does not cause any strong modifications of sexual reproduction. Consequently, it is not clear how the high infection rates of the bacterium in populations of this species are maintained. The wMel strain is classified into two groups of genotypes - wMel and wMelCS. The wMel genotype is ubiquitous in populations, while wMelCS is rare. In this study, we analyzed fitness-related traits in isofemale lines from the unique natural population from Uman (Central Ukraine), in which we observed preservation of the rare wMelCS genotype despite the fluctuations of infection rates between years. We analyzed these effects of Wolbachia genotype and host genetic background on important fitness parameters such as sensitivity to cold and oxidative stress, female fecundity and lifespan. We found that, in the studied population, Wolbachia had an impact on fitness traits only in certain Drosophila genotypes. Positive effects were manifested in the alterations of fecundity, but at the cost of reduced lifespan and resistance to stress. Based on these findings, we conclude that the effect of bacteria on fitness and stress related traits is context-dependent and is modified by the host genotype, at least in the lines established from the Uman population.

Given the recent climate changes and their impact on the Antarctic Peninsula ecosystems, the emergence of invasive species, and increased tourism activity in this region, monitoring changes in the habitats of species native to the Antarctic Peninsula region is necessary. One such species is the Antarctic midge Belgica antarctica (Chironomidae). This insect is endemic to the Antarctic Peninsula and adjacent islands. Thorough studies of changes in the range of this species have not been performed in recent decades. In this study, we present the area of Belgica antarctica according to the collections of biological samples during 2007–2021 (XII, XIV, XVI, XXIV, and XXV Ukrainian Antarctic Expeditions). This Antarctic midge was recorded at 26 localities on the Antarctic Peninsula and 212 localities on 55 surrounding islands between 66°08′38.4′′ S, 65°43′37.1′′ W (Cape Evensen, Stresher Peninsula, opposite the Marie Island, west coast of Graham Land) and 62°11′44.7′′ S, 58°57′40.6′′ W (King George Island, South Shetland Islands) from south-west to north-east.

Ukraine is on the invasion front of spotted-wing Drosophila suzuki (Matsumura, 1931) spreading in Europe. Despite this globally important pest was confirmed only on the southernmost tip of its territory, recently published species distribution models expect its occurrence also in other Ukrainian regions. Therefore, we conducted two-year monitoring (2018-2019) during the whole fruit ripening season; samples were collected on the whole Ukrainian territory; standard bait traps and active capture by an insect net were employed. Individuals of the species were recorded only at the end of the vegetation season (August–October) and only in the westernmost part of Ukraine (Transcarpathian region); in the region predicted by recent ecological niche modeling. The late occurrence of D. suzuki probably reflects the presence of suitable food/fruit for the larvae at the end of the growing season. Our results confirm the importance of monitoring of this pest, together with the investigation of factors that may affect its invasion.

The rhizosphere microbiome of the native Antarctic hairgrass Deschampsia antarctica from the central maritime Antarctic was investigated using 16S RNA metagenomics and compared to those of the second native Antarctic plant Colobanthus quitensis and closely related temperate D. cespitosa. The rhizosphere microbial communities of D. antarctica and D. cespitosa had high taxon richness, while that of C. quitensis had markedly lower diversity. The majority of bacteria in the rhizosphere communities of the hairgrass were affiliated to Proteobacteria, Bacteroidetes, and Actinobacteria. The rhizosphere of C. quitensis was dominated by Actinobacteria. All microbial communities included high proportions of unique amplicon sequence variants (ASVs) and there was high heterogeneity between samples at the ASV level. The soil parameters examined did not explain this heterogeneity. Bacteria belonging to Actinobacteria, Bacteroidetes, and Proteobacteria were sensitive to fluctuations in the soil surface temperature. The values of the United Soil Surface Temperature Influence Index (UTII, I

Simple Summary The chironomid midge Belgica antarctica Jacobs is endemic to the western Antarctic Peninsula and South Shetland Islands. We provide the first detailed photomicrographic images of the fourth-instar larval head capsule and posterior parapods. We assessed variation in the morphology of larvae from two different collection locations off the coast of the western Antarctic Peninsula and compared it with that available in the literature. A number of differences were identified relating to the size of the larvae, the number of teeth on the mandibles, the number of antennal segments and the length of the antennal blade. Malformations of the mandible and mentum are reported for the first time in this species. Abstract The external morphology of the fourth-instar larva of the Antarctic endemic chironomid midge Belgica antarctica is described. Larvae were collected from Jougla Point (Wiencke Island) and an un-named island close to Enterprise Island, off the coast of the western Antarctic Peninsula. Light microscopy was used to examine and document photographically the structures of the mouthparts (mandible, mentum, premandible, labrum), antennae, pecten epipharyngis, clypeus, frontal apotome and posterior parapods. Measurements of the mouthparts are presented. The data obtained are compared with that available in the literature. A number of differences were identified relating to the size of the larvae, the number of teeth on the mandibles, the number of antennal segments and the length of the antennal blade. Malformations of the mandible and mentum are reported for the first time in this species. Features of larvae of taxonomic value that can be used to determine the species in larval stages are presented. These are of utility in using the larvae to reveal relationships with other species. Larvae are also important in ecological and genotoxicological studies, which require accurate species level identification.

Fullerenes have attracted attention since their discovery as structural units of complex carbon nanostructures capable of transporting drugs and macromolecules. As such artificial nanomaterials are applied in biology and medicine, they are routinely scrutinized for their effects on living organisms. The results of such studies range from direct destabilizing effects on DNA molecules to amelioration of the toxic effects of known genotoxic agents. We tested the effect of buckminsterfullerene (C60) on Drosophila melanogaster at DNA, tissue and organism levels. The water-soluble pristine C60 fullerene at the concentration of 20 μg/ml and 40 μg/ml leads to the activation of the mus209 gene in D. melanogaster larvae salivary glands, which can indicate higher levels of DNA damage. However, the absence of effects at the cell and organismal level could be explained by the activation of repair systems or by active elimination of damaged cells.

In this study we characterized allele frequencies of 15 autosomal STR loci, including 13 CODIS (D8S1179, D21S11, D7S820, CSF1P0, D3S1358, TH01, D13S317, D16S539, vWA, TPOX, D18S51, D5S818, FGA) and...

The origin of one from two native vascular plants in Antarctic, the Antarctic hairgrass (Deschampsia antarctic E. Desv.) (Poaceae), remains unclear. Molecular genetic analyses have demonstrated low genetic heterogeneity among representatives of this species. The search for new marker nucleotide sequences of the Antarctic hairgrass is justified, which would be useful in clarifying the phylogeographic origin, heterogeneity and population dynamics of D. antarctica. Here we report the results of a comparative analysis of the introns of β-tubulin genes for several populations of the Antarctic hairgrass across the maritime Antarctic. We demonstrate that the first intron of the β-tubulin gene contain markers capable of discriminating D. antarctica subpopulations in the maritime Antarctic. The sequence of the first intron of the β-tubulin gene can therefore be used for more detailed population genetics studies of D. antarctica.

Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last 20 years. A major challenge is the integration of these disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution and population structure of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 population samples from over 100 locations in >20 countries on four continents based on a combination of 121 unpublished and 150 previously published genomic datasets. Several of these locations have been sampled at different seasons across multiple years. This dataset, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental meta-data. A web-based genome browser and web portal provide easy access to the SNP dataset. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan dataset. Our resource will enable population geneticists to analyze spatio-temporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.

To advance our understanding of adaptation to temporally varying selection pressures, we identified signatures of seasonal adaptation occurring in parallel among Drosophila melanogaster populations. Specifically, we estimated allele frequencies genome-wide from flies sampled early and late in the growing season from 20 widely dispersed populations. We identified parallel seasonal allele frequency shifts across North America and Europe, demonstrating that seasonal adaptation is a general phenomenon of temperate fly populations. Seasonally fluctuating polymorphisms are enriched in large chromosomal inversions, and we find a broad concordance between seasonal and spatial allele frequency change. The direction of allele frequency change at seasonally variable polymorphisms can be predicted by weather conditions in the weeks prior to sampling, linking the environment and the genomic response to selection. Our results suggest that fluctuating selection is an important evolutionary force affecting patterns of genetic variation in Drosophila.

Drosophila melanogaster is an important model for antiviral immunity in arthropods, but very few DNA viruses have been described from the family Drosophilidae. This deficiency limits our opportunity to use natural host-pathogen combinations in experimental studies, and may bias our understanding of the Drosophila virome. Here, we report fourteen DNA viruses detected in a metagenomic analysis of 6668 pool-sequenced Drosophila, sampled from forty-seven European locations between 2014 and 2016. These include three new nudiviruses, a new and divergent entomopoxvirus, a virus related to Leptopilina boulardi filamentous virus, and a virus related to Musca domestica salivary gland hypertrophy virus. We also find an endogenous genomic copy of galbut virus, a double-stranded RNA partitivirus, segregating at very low frequency. Remarkably, we find that Drosophila Vesanto virus, a small DNA virus previously described as a bidnavirus, may be composed of up to twelve segments and thus represent a new lineage of segmented DNA viruses. Two of the DNA viruses, Drosophila Kallithea nudivirus and Drosophila Vesanto virus are relatively common, found in 2 per cent or more of wild flies. The others are rare, with many likely to be represented by a single infected fly. We find that virus prevalence in Europe reflects the prevalence seen in publicly available datasets, with Drosophila Kallithea nudivirus and Drosophila Vesanto virus the only ones commonly detectable in public data from wild-caught flies and large population cages, and the other viruses being rare or absent. These analyses suggest that DNA viruses are at lower prevalence than RNA viruses in D.melanogaster, and may be less likely to persist in laboratory cultures. Our findings go some way to redressing an earlier bias toward RNA virus studies in Drosophila, and lay the foundation needed to harness the power of Drosophila as a model system for the study of DNA viruses., M.W. was supported by the UK Natural Environmental Research Council through the E3 doctoral training programme (NE/L002558/1), and S.R. was supported by Wellcome Trust PhD programme (108905/Z/15/Z). A.B. received funding from BBSRC (grant number BB/P00685X/1). T.F. received funding from Swiss National Science Foundation (grant numbers 31003A-182262, PP00P3_165836, and PP00P3_133641/1). C.G. received funding from Agence Nationale de la Recherche (grant number ANR-15-CE32-0011-01). J.G. received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (H2020-ERC-2014-CoG-647900) and from the Fundación Española para la Ciencia y la Tecnologia-Ministerio de Economía y Competitividad (FCT-15-10187). S.G. received funding from Deutsche Forschungsgemeinschaft (grant number GR 4495/2). M.K. received funding from Academy of Finland projects (268214 and 322980). M.K. received funding from Austrian Science Fund (FWF; grant number P32275). V.L. received funding from Danish Research council for natural Sciences (FNU; grant number 4002-00113B). B.S.O. received funding from the Scientific and Technological Research Council of Turkey (TUBITAK; grant number 214Z238). J.P. received funding from Deutsche Forschungsgemeinschaft (grant number PA 903/8). M.S.-R., M.S.V., and M.J. received funding from the Ministry of Education, Science and Technological Development of the Republic of Serbia (grant number 451-03-68/2020-14/200178). F.S. received funding from Deutsche Forschungsgemeinschaft (grant number STA1154/4-1; Projektnummer 408908608). M.T., A.P., and K.E. received funding from the Ministry of Education, Science and Technological Development of the Republic of Serbia (grant number 451-03-68/2020-14/200007). The DrosEU consortium has been funded by a Special Topics Network (STN) grant by the European Society of Evolutionary Biology (ESEB).

Endophytic bacteria, recognized for their beneficial effects on plant development and adaptation, can facilitate the survival of Antarctic plants in severe environments. Here we studied endophytes of the vascular plant Deschampsia antarctica Ė. Desv. from two distantly located regions in the maritime Antarctic: King George Island (South Shetland Islands) and Galindez Island (Argentine Islands). Bacterial group-specific PCR indicated presence of Alphaproteobacteria , Betaproteobacteria , Gammaproteobacteria , Firmicutes, Cytophaga-Flavobacteria and Actinobacteria in root and leaf endosphere of D. antarctica sampled at four distinct sites of both locations . The diversity of endophytic bacteria was significantly higher in the leaves compared to the roots in plants from Galindez Island. Similarly, the diversity of endophytes was higher in the leaves rather than roots of plants from the King George Island. Twelve bacterial species were isolated from roots of D. antarctica of Galindez Island (the Karpaty Ridge and the Meteo Point) and identified by sequencing the 16S rRNA gene. Isolates were dominated by the Pseudomonas genus, followed by the genera Bacillus and Micrococcus. The vast majority of the isolates exhibited cellulase and pectinase activities, however, Bacillus spp. expressed neither of them, suggesting lack of genetic flow of these traits in endophytic bacilli in the maritime Antarctic. Pseudomonas sp. IMBG305 promoted an increase in the leaf number in most of the treated plant genotypes when compared with non-inoculated plants, and a rapid vegetation period of D. antarctica cultured in vitro , albeit the length of leaves in the treated plants was significantly lower, and flavonoid content leveled off in all treated plants . D. antarctica is known to develop diverse ecotypes with regard to ecological conditions, such as organic input, moisture or wind exposition. The D. antarctica phenotype could be extended further through the endophyte colonization, since phenotypic changes were observed in the inoculated D. antarctica plants grown in vitro in our study . Herewith, endophytes can contribute to plant phenotypic plasticity, potentially beneficial for adaptation of D. antarctica .

Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last years. A major challenge is the integration of disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 previously published and unpublished population samples from over 100 locations in > 20 countries on four continents. Several of these locations have been sampled at different seasons across multiple years. This dataset, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental meta-data. A web-based genome browser and web portal provide easy access to the SNP dataset. We further provide guidelines on how to use Pool-Seq data for model-based demographic inference. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan dataset. Our resource will enable population geneticists to analyze spatio-temporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail., DrosEU is funded by a Special Topic Networks (STN) grant from the European Society for Evolutionary Biology (ESEB). MK (M. Kapun) was supported by the Austrian Science Foundation (grant no. FWF P32275); JG by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (H2020-ERC-2014-CoG-647900) and by the Spanish Ministry of Science and Innovation (BFU-2011-24397); TF by the Swiss National Science Foundation (SNSF grants PP00P3_133641, PP00P3_165836, and 31003A_182262) and a Mercator Fellowship from the German Research Foundation (DFG), held as a EvoPAD Visiting Professor at the Institute for Evolution and Biodiversity, University of Münster; AOB by the National Institutes of Health (R35 GM119686); MK (M. Kankare) by Academy of Finland grant 322980; VL by Danish Natural Science Research Council (FNU) grant 4002-00113B; FS Deutsche Forschungsgemeinschaft (DFG) grant STA1154/4-1, Project 408908608; JP by the Deutsche Forschungsgemeinschaft Projects 274388701 and 347368302; AU by FPI fellowship (BES-2012-052999); ET Israel Science Foundation (ISF) grant 1737/17; MSV, MSR and MJ by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200178); AP, KE and MT by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200007); and TM NSERC grant RGPIN-2018-05551.

Drosophila melanogasteris an important model for antiviral immunity in arthropods, but very few DNA viruses have been described from the family Drosophilidae. This deficiency limits our opportunity to use natural host-pathogen combinations in experimental studies, and may bias our understanding of theDrosophilavirome. Here we report fourteen DNA viruses detected in a metagenomic analysis of approximately 6500 pool-sequencedDrosophila, sampled from 47 European locations between 2014 and 2016. These include three new Nudiviruses, a new and divergent Entomopox virus, a virus related toLeptopilina boulardifilamentous virus, and a virus related toMusca domesticasalivary gland hypertrophy virus. We also find an endogenous genomic copy of Galbut virus, a dsRNA Partitivirus, segregating at very low frequency. Remarkably, we find thatDrosophilaVesanto virus, a small DNA virus previously described as a Bidnavirus, may be composed of up to 12 segments and represent a new lineage of segmented DNA viruses. Two of the DNA viruses,DrosophilaKallithea nudivirus andDrosophilaVesanto virus are relatively common, found in 2% or more of wild flies. The others are rare, with many likely to be represented by a single infected fly. We find that virus prevalence in Europe reflects the prevalence seen in publicly-available datasets, withDrosophilaKallithea nudivirus andDrosophilaVesanto virus the only ones commonly detectable in public data from wild-caught flies and large population cages, and the other viruses being rare or absent. These analyses suggest that DNA viruses are at lower prevalence than RNA viruses inD. melanogaster, and may be less likely to persist in laboratory cultures. Our findings go some way to redressing an earlier bias toward RNA virus studies inDrosophila, and lay the foundation needed to harness the power ofDrosophilaas a model system for the study of DNA viruses.

Aim. To evaluate the toxicity and genotoxicity of Ag2S quantum dots that had been synthesized by the mycelium of the fungus Pleurotus ostreatus on Drosophila melanogaster. Methods. The toxicity of nanoparticles was determined by assessing the survival rate of imagos and larvae. Genotoxicity was studied in the reparation test. The influence of nanoparticles on the development of the D. melanogaster reproductive system was determined by evaluating the number of ovariols. Results. The toxic effects of ionic silver and the absence of such effects in biosynthetic Ag2S nanoparticles had been shown. The negative influence of biosynthesized Ag2S nanoparticles and biomaterials and ionic silver on the development of D. melanogaster reproductive system had been revealed. There was no genotoxic effect for all investigated specimens. Conclusions. Ag2S biosynthesized quantum dots do not have a toxic and genotoxic effects on D. melanogaster at the concentration of 1.5 mg/ml. However, the action of Ag2S (salt), the biological matrix Pleurotus and biosynthetic Ag2S nanoparticles leads to a decrease in the number of ovariols. Keywords: Ag2S nanoparticles, D. melanogaster, toxicity, genotoxicity.

Aim. To determine the frequency of TP53 polymorphic variants in bladder cancer patients and define possible association of this polymorphism with a bladder cancer in Ukrainians patients. Methods. The genotypes of TP53 gene at codon 72 were detected by PCR with allele specific primers. We investigated Arg72Pro polymorphism in 114 DNA samples of patients with bladder cancer. The PCR-amplified DNA products were subjected to electrophoresis in 3 % agarose. Results. The distribution of genotypes in group of patients with a bladder cancer was: Arg/Arg – 59.6 % (n=68), Arg/Pro – 40.4 % (n=46), Pro/Pro – 0 % (n=0). Genotype frequencies in patients (χ2=7.28, p=0.0007) weren’t in agreement with Hardy-Weinberg equilibrium. There were significant differences in the frequency of genotypes between the healthy individuals and the cancer group patients. Our result showed that patients with bladder cancer had a significantly higher frequency of Arg/Arg (F=42.7, p

Aim. To study the influence of different temperatures on larval stage on the development duration and life expectancy of Drosophila melanogaster imago. Methods. The statistical significance of the indicators was determined by one-way ANOVA followed by Tukey HSD post-hoc tests to evaluate significance of differences between groups. Results. The development duration of imagoes significantly increased by 1.7 times when the developmental temperature decreased from 27.5 to 20.0°С. The average and maximum lifespan of the flies was maximum at a temperature of 22.5°С. The lifespan of fruit flies was significantly decreased compared to control (25.0°С) at a developmental temperature of 20.0°C and above 22.5°C. Conclusions. The obtained data suggest that developmental temperature significantly affects the lifespan of the flies. It likely is a physiological optimum of the temperature of development, in which life expectancy is maximal. Probably, this is due to the fact that at optimal temperature, the Drosophila development is most complete and their viability is highest.Keywords: Drosophila melanogaster, development, lifespan, temperature, larval stage.

Aim. To investigate the life expectancy and reproductive activity of Drosophila melanogaster that developed in conditions of increased larval density. Methods. Mean and maximum life span were determined in males and females in the different experimental groups. The reproductive activity was evaluated by counting the total number of eggs laid by one female per day. Results. A significant increase of the mean life span compared to control was observed in adults that hatched from pupae during the first and second days after the beginning of the emergence: males — 24 % and 23.5 %, females — 23.8 % and 29.3 % respectively. The level of reproductive activity (fecundity) is statistically lower in two groups which hatched last. Conclusions. Based on the results obtained, we suggest that development in conditions of increased larval density can lead to increase in the life span of D. melanogaster.Keywords: life span, Drosophila melanogaster, reproductive activity, development.

In the present paper, we compare how the kelp gull, Larus dominicanus, utilizes various nest building materials, particularly vascular plants, bryophytes, lichens and other components, in the Fildes Peninsula area (King George Island) and on the Argentine Islands area. In both areas, nest material primarily consisted of the Antarctic hairgrass (Deschampsia antarctica), bryophytes, lichens, feathers, limpets, and algae. Our study reveals area-specific differences in the utilization of plants for nest building related to local conditions during the nesting season. In the Fildes area, vegetation emerges from under the winter snow cover earlier in the spring, giving the gulls greater choice locally, meaning that the gulls need not resort to long distance material transfer. Here, mosses and lichens dominate in the nest material, likely collected from the nearby vegetation formations. The Antarctic hairgrass in these conditions is mostly found in nests located directly within hairgrass formations. However, on the more southern Argentine Islands, kelp gulls routinely use D. antarctica and some mosses, transferring them from coastal hill tops where snow generally disappears earlier. Here, the gulls appear to be selective still, as they rarely use some mosses, such as Polytrichum strictum, that are abundant near the nesting locations. In the Argentine Islands area, we documented long-range transfer of the Antarctic hairgrass and some other vegetation materials from places of abundance to bare rocks of low islands lacking developed vegetation. This demonstrates the potential of the gulls to serve as dispersal and gene pool exchange agents for the local terrestrial biota in the maritime Antarctic, especially between highly isolated populations from small islands and ice-free areas.

Background In Ukraine, 3539 patients were diagnosed with ovarian cancer in 2018, and more than half of these cases were lethal. One of the risk factors for ovarian cancer development are the alterations in the breast cancer gene 1 (BRCA1). Among these alterations, the most frequent is the germline mutation 185delAG and the frameshift mutation 4153delA. The frequencies of these mutations were identified earlier (Tsip et al., 2019) in ovarian cancer patients from Ukraine. Objective The present study aimed to evaluate the frequency of the mutations 185delAG and 4153delA in the BRCA1 gene in an unselected ovarian cancer patient's cohort from Ukraine. Materials and methods We screened 663 ovarian cancer patients diagnosed at different ages by routine allele-specific polymerase chain reaction (PCR) and real-time PCR. Results 13 cases of two BRCA1 mutations were detected (4 cases of 185delAG and 9 cases of 4153delA). Conclusions Out of 663 ovarian cancer patients, 4 cases with 185delAG and 9 cases of 4153delA in the BRCA1 gene were identified, giving a frequency of 2.0 ± 0.5%. Our data shows that the previous mutations screening results in ovarian cancer patients from Ukraine were higher than in the present study.

Tardigrada in Antarctic regions are poorly known. The aim of this study was to examine for tardigrades the nests material of the kelp gull (Larus dominicanus Lichtenstein, 1823) in maritime Antarctic and discuss the possible ways of migration and dispersion of tardigrades by birds. We also discuss the influence of bird’s guano on the communities of microscopic invertebrates (mainly tardigrades). In the positive samples (mainly bryophytes and lichens) of seven Larus dominicanus nests, collected on Ardley Island (near Fildes Peninsula) and Argentine Islands, ca. 850 tardigrades and their eggs were found. In total, 13 taxa (including Ramajendas sp.) were identified, and four are new to science: Bryodelphax olszanowskii sp. nov., Diphascon puchalskii sp. nov., D. rudnickii sp. nov. and Hypsibius conwentzii sp. nov.. Bryodelphax olszanowskii sp. nov. differs from known Bryodelphax species in the weglarskae group mainly by having a different ventral plate configuration. Belonging to the pingue group, D. puchalskii sp. nov. differs from other species by some quantitative characters and D. rudnickii sp. nov. by having the first and second macroplacoids situated very close to each other. Hypsibius conwentzii sp. nov. differs from other species of the genus Hypsibius, with two macroplacoids and septulum, by some morphological and morphometric characters. Summarizing, Antarctic tardigrades are a very diverse group, and birds can be responsible for translocation of small invertebrates (including tardigrades) inside of various parts of plants and lichens. They also deposit large amounts of guano, which provides a lot of nutrients for poor tundra ecosystems and support small invertebrate communities.

Ovarian cancer is the seventh most common cancer in women worldwide and the leading cause of gynecological malignant diseases-related deaths in women. The most significant risk factor for ovarian cancer is an inherited genetic mutation in one of two genes: breast cancer gene 1 (BRCA1) or breast cancer gene 2 (BRCA2). The germline mutation c.5266dupC (also known as 5382insC or 5385insC) is the most common mutation among Slavic patients with breast and/or ovarian cancer. Missense mutation c.181T > G (also known as 300T > G or p.C61G) is regarded as the founder change in many Central European countries. We screened 306 ovarian cancer patients diagnosed at different ages by mutagenically separated polymerase chain reaction (PCR) and real-time PCR. A total of 25 BRCA1 mutations were detected (18 cases of 5382insC and 7 cases of 300 T > G). The frequency of the BRCA1 5382insC mutation is similar in breast and ovarian cancer patients from Ukraine, but the frequency of 300T > G was estimated in Ukraine at first time.

Drosophila suzukii, commonly known as the spotted-wing Drosophila, is an invasive polyphagous fruit pest, which has emerged as a global threat to agriculture in the Americas and in Europe. Due to the rapid spread, great economic losses and its pest behavior, D. suzukii represents a powerful model for invasion biology and pest management studies. However, its current European distribution, invasion routes and levels of genetic diversity in populations of D. suzukii are poorly understood. We present the first report of D. suzukii from Ukraine, with the invasion likely occurring close to 2014. The pattern of genetic variation at cytochrome oxidase I among D. suzukii populations from Europe, USA and Asia reveals comparatively high genetic diversity in the Ukrainian population of this pest species, suggesting a complex invasion scenario from multiple sources. Further monitoring patterns of genetic variation across space and time, to better understand the invasion routes of this invasive insect pest, will be an essential part for developing successful pest management strategies.

The vascular plantDeschampsia antarcticasamples were collected for endophytic bacteria study from two regions in the maritime Antarctic 400 km distant from one another: Point Thomas oasis (King George Island) and Argentine Islands (Galindez Island). The endophytes were isolated from roots and leaves ofD. antarctica, cultivated and identified by using a partial sequencing of the 16S rRNA gene served as a phylomarker. Endophyte isolates from two sites of Galindez Island were represented mainly byPseudomonasspecies and byGammaproteobacteria, FirmicutesandActinobacteria. The vast majority of the isolates had specific for endophytes cellulase and pectinase activities, however,Bacillusspp. did not express both activities. A group-specific PCR screening at the four sites of Galindez Island and two sites of King George Island, indicatedAlphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, Cytophaga-FlavobacteriaandActinobacteria.Notably, the number of endophytic bacteria taxa was significantly larger in leaves than in roots of plants.

Prostate cancer (PCa) is the second most common malignancy and the sixth leading cause of cancer-related death among men worldwide. Prostate carcinogenesis is driven by the accumulation of genetic and epigenetic aberrations, which regulate cancer cell transition between a stem- and nonstem-cell state and accelerate tumor evolution. Elevated expression of enhancer of zeste homolog 2 (EZH2) histone methyltransferase, a core member of the polycomb repressive complex 2 (PRC2), results in cancer progression through histone methylation-driven tumor cells dedifferentiation. Previous studies demonstrated that tumor suppressor breast cancer 1 (BRCA1) is a negative regulator of PRC2-dependent H3K27 methylation. Our recent studies revealed that inhibition of EZH2-mediated histone methylation radiosensitizes prostate cancer stem cells (CSCs) population. However, the link between BRCA1 and EZH2 in regulation of prostate CSCs remains elusive. Present study demonstrated that BRCA1 and EZH2 are coregulated in patients' tumors and PCa cell lines, and cooperate in regulation of CSC phenotype and properties. Knockdown of BRCA1 expression significantly increases the number and the size of tumor spheres. Inhibition of BRCA1 and EZH2 expression leads to an increase of aldehyde dehydrogenase (ALDH)-positive cell population that is, at least partially, attributed to the upregulation of ALDH1A3 protein. Treatment with a global histone methylation inhibitor 3-Deazaneplanocin A abrogates this regulation, downregulates BRCA1 and EZH2 expression and has an inhibitory effect on the tumorigenic properties of radioresistant PCa cells in vivo. We found that EZH2/BRCA1 signaling mechanisms play an important role in the maintenance of prostate CSC properties and may be a promising target for tumor treatment.

We studied a set of Drosophila melanogaster strains that could be potentially suitable for testing a variety of mutagenic factors. Their genomes contained insertions of the enhancer trap P {lacW}-in which the activity of the LacZ reporter is under the control of the reparation genes’ regulatory region. We demonstrated that the beta-galactosidase reporter, which is encoded by insertion of P {lacW} element in the gene mus209, is induced by irradiation in the cells of the salivary glands and wing imaginal discs. Despite the fact that the reporting coloration is not associated with the dose of radiation treatment, we found that the induction threshold of the reporter is different for these tissues. Thus, coloration in salivary glands is detectable after the dose of 200 rad and above, whereas the imaginal discs get colored with 500 rads and above. Thereby, multiple thresholds for induction of the reporter in the various tissues allow approximating the received dose.

There is increasing evidence that stress during development can affect adult-life health status and longevity. In the present study, we examined life span (LS), fly weight, fecundity and expression levels of longevity-associated genes (Hsp70, InR, dSir2, dTOR and dFOXO) in adult Drosophila melanogaster flies reared in normal [low density (LD), ~ 300–400 eggs per jar] or crowded [high density (HD), more than 3000 eggs per jar] conditions by using the order (day) of emergence as an index of the developmental duration (HD1-5 groups). Developmental time showed a significant trend to increase while weight showed a significant trend to decrease with increasing the timing of emergence. In both males and females eclosed during first 2 days in HD conditions (HD1 and HD2 groups), both mean and maximum LSs were significantly increased in comparison to LD group. In males, mean LS was increased by 24.0% and 23.5% in HD1 and HD2 groups, respectively. In females, corresponding increments in mean LS were 23.8% (HD1 group) and 29.3% (HD2 group). In HD groups, a strong negative association with developmental time has been found for both male and female mean and male maximum LSs; no association with growth rate was observed for female maximum LS. The female reproductive activity (fecundity) tended to decrease with subsequent days of eclosion. In HD groups, the levels of expression of all studied longevity-associated genes tended to increase with the timing of eclosion in males; no differences were observed in females. On the basis of findings obtained, it can be assumed that the development in conditions of larval overpopulation (if not too extended) could trigger hormetic response thereby extending the longevity. Further studies are, however, needed to confirm this assumption.

To advance our understanding of adaptation to temporally varying selection pressures, we identified signatures of seasonal adaptation occurring in parallel amongDrosophila melanogasterpopulations. Specifically, we estimated allele frequencies genome-wide from flies sampled early and late in the growing season from 20 widely dispersed populations. We identified parallel seasonal allele frequency shifts across North America and Europe, demonstrating that seasonal adaptation is a general phenomenon of temperate fly populations. Seasonally fluctuating polymorphisms are enriched in large chromosomal inversions and we find a broad concordance between seasonal and spatial allele frequency change. The direction of allele frequency change at seasonally variable polymorphisms can be predicted by weather conditions in the weeks prior to sampling, linking the environment and the genomic response to selection. Our results suggest that fluctuating selection is an important evolutionary force affecting patterns of genetic variation inDrosophila.

Antarctica is an isolated continent whose conditions challenge the survival of living organisms. High levels of endemism are now known in many Antarctic organisms, including algae, tardigrades, nematodes and microarthropods. Bdelloid rotifers are a key, widespread and abundant group of Antarctic microscopic invertebrates. However, their diversity, regional distribution and endemism have received little attention until recently. We provide the first authoritative review on Antarctic Bdelloidea, based on published data and new collections. Our analysis reveals the extreme levels of bdelloid endemism in Antarctica. Sixty-six bdelloid morphospecies are now confirmed from the continent, and 83–91 putative species are identified using molecular approaches (depending on the delimitation method used). Twelve previously unknown species are described based on both morphology and molecular analyses. Molecular analyses indicate that only two putative species found in Antarctica proved to be truly cosmopolitan. The level of endemism based on the available data set (95%) is higher than that in any other continent, with many bdelloid species occurring only in maritime or continental Antarctica. These findings are consistent with the long-term presence of Bdelloidea in Antarctica, with their considerable isolation facilitating intraregional radiation, providing further evidence that does not support the microbial global ubiquity hypothesis that “everything is everywhere."

The fruit flies Drosophila simulans Sturtevant, 1919 and Drosophila melanogaster Meigen, 1830 are sibling species that occupy similar niches. However, unlike D. simulans, D. melanogaster has spread far beyond tropical and subtropical regions deep into temperate climate zones. A number of invasion events by D. simulans into temperate climate zones have been reported; however, its ability to overwinter and establish local populations in these areas is disputed. Here, we report the wide dispersal of D. simulans in mixed populations with D. melanogaster in Ukraine. Drosophila simulans flies found in Ukraine belong to the siII mtDNA haplogroup and are infected with maternally inherited intracellular symbiotic bacteria of the genus Wolbachia Hertig, 1936 of the strain wRi. These genetic markers indicate a common origin of the Ukrainian D. simulans flies from a subgroup of the species found to invade other temperate climate areas worldwide. Here, we report for the first time detection of D. simulans flies early in the breeding season in a temperate climate area with severe winter conditions. We also report a moderate negative relationship between relative abundance of D. simulans and mean temperature in the month of sampling reflecting this species’ known lower tolerance of high temperatures.

Native species of the Antarctic Deschampsia antarctica and Colobanthus quitensis exist at the limits of survival of vascular plants. Fundamental adaptations to abiotic environmental factors that qualitatively distinguish them from the other vascular plants of extreme regions, namely temperature, ultraviolet radiation hardiness, and their genetic plasticity in the changeable environment are discussed.

OBJECTIVE To estimate frequencies of polymorphic variants of TP53 codon 72 in the Ukrainian population. MATERIALS AND METHODS We determined the allele frequencies for 148 healthy people. Genotyping was performed by allele specific polymerase chain reaction. RESULTS We identified 31 individuals (20.9 %) with Arg/Arg genotype, Arg/Pro genotype was identified for 116 indi viduals (78.4 %), whereas genotype Pro/Pro was rare and was found in one person only (0.7 %). Genotype distribu tions were not within Hardy Weinberg equilibrium (χ2 = 59,7, p < 0.0001). CONCLUSIONS Arg and Pro allele frequencies in the population of Ukraine are 60 and 40 % respectively, which is sig nificantly differ from the frequencies described in the literature for Poland, the Czech Republic, the USA and Brazil.

P element is a DNA transposon, known to spread in genome using transposase activity. Its activity is tissue-specific and normally observed at high temperatures within 24°C to 29°C. Here, we present a predicted RNA secondary structure domain of P element pre-mRNA which could potentially regulate the temperature sensitivity of the P element activity. In canonical P elements, the structure is a small hairpin with double-helical part interrupted by a symmetric loop and a mismatch. In M type P elements, the A.A mismatch is substituted by an A-U base pair, stabilizing the structure. The hairpin structure covers the region involving the IVS-3 5′ splice site and both pseudo-splice sites F1 and F2. While the IVS-3 and F1 binding sites of U1 snRNA are located in the double-stranded part of the structure, the F2 site is exposed in the hairpin loop. The formation of this structure may interfere with landing of U1 snRNA on IVS-3 site, while F2 is positioned for the interaction. Alignment of P element sequences supports the proposed existence of the hairpin, showing high similarity for this region. The hairpin structure, stable at low temperatures, may prevent correct IVS-3 splicing. Conversely, temperature-induced destabilization of the hairpin structure may result in the splicing at the proper IVS-3 splice site. Taking into account the increasing amount of data demonstrating the important influence of RNA folding on phenotypes determined by alternative splicing a model for possible regulation of the activity of mobile elements by pre-mRNA secondary structure seems intriguing. Предсказана вторичная структура пре-мРНК P-элемента, которая, возможно, регулирует его активность и температурную чувствительность. Структура представляет собой шпильку, более стабильную в Р-элементах М-типа, в сравнении с каноническими. Регион, образующий шпильку, находится в области 5’ сайта сплайсинга третьего интрона (IVS-3), включая оба описанных псевдо-сайта сплайсинга - F1 и F2. В то время как истинный сайт и F1 расположены, главным образом, в двухцепочечной области шпильки, F2 - экспонирован в петле. Выравнивание последовательностей Р-элементов продемонстрировало высокую степень сходства для указанного региона, что свидетельствует в пользу существования предсказанной структуры. Формирование шпильки, по нашему мнению, может препятствовать связыванию U1 snRNA с истинным сайтом сплайсинга, и, напротив, индуцированная температурой дестабилизация шпильки может приводить к корректному сплайсингу IVS-3. Таким образом, предложена гипотеза о влиянии вторичной структуры пре-мРНК мобильного элемента на его активность. Передбачена вторинна структура пре-мРНК Р-елемента, що, можливо, регулює його активність та температурну чутливість. Структура являє собою шпильку, більш стабільну у Р-елементах М-типу, порівняно з канонічними. Регіон, що утворює шпильку розташований в області 5’ сайта сплайсинга третього інтрону (IVS-3), включає обидва відомих псевдо-сайта сплайсингу - F1 та F2. При цьому 5’ сайт сплайсингу IVS-3 та F1псевдо-сайт знаходяться у дволанцюговій частині шпильки, а F2 є єкспонованим у петлі. Вирівнювання послідовностей Р-елементів продемонструвало високий рівень подібності для вказаного регіону, що свідчить на користь існування передбаченої структури. Формування шпильки, на нашу думку, може перешкоджати зв’язуванню U1 snRNA з 5’ сайтом сплайсингу IVS-3, і, навпаки, індукована температурою дестабілізація шпильки може сприяти корректному сплайсингу третього інтрону. Таким чином, запропонована гіпотеза про вплив вторинної структури пре-мРНК мобільного елементу на його активність.

TheDrosophila melanogaster Ptransposable element provides one of the best cases of horizontal transfer of a mobile DNA sequence in eukaryotes. Invasion of natural populations by thePelement has led to a syndrome of phenotypes known as P-M hybrid dysgenesis that emerges when strains differing in theirPelement composition mate and produce offspring. Despite extensive research on many aspects ofPelement biology, many questions remain about the genomic basis of variation in P-M dysgenesis phenotypes in natural populations. Here we compare gonadal dysgenesis phenotypes and genomicPelement predictions for isofemale strains obtained from three worldwide populations ofD. melanogasterto illuminate the molecular basis of natural variation in cytotype status. We show that the number of predictedPelement insertions in genome sequences from isofemale strains is highly correlated across different bioinformatics methods, but the absolute number of insertions per strain is sensitive to method and filtering strategies. Regardless of method used, we find that the number of euchromaticPelement insertions predicted per strain varies significantly across populations, with strains from a North American population having fewerPelement insertions than strains from populations sampled in Europe or Africa. Despite these geographic differences, numbers of euchromaticPelement insertions are not strongly correlated with the degree of gonadal dysgenesis exhibited by an isofemale strain. Thus, variation inPelement insertion numbers across different populations does not necessarily lead to corresponding geographic differences in gonadal dysgenesis phenotypes. Additionally, we show that pool-seq samples can uncover population differences in the number ofPelement insertions observed from isofemale lines, but that efforts to rigorously detect differences in the number ofPelements across populations using pool-seq data must properly control for read depth per strain. Our work supports the view that euchromaticPelement copy number is not sufficient to explain variation in gonadal dysgenesis across strains ofD. melanogaster, and informs future efforts to decode the genomic basis of geographic and temporal differences inPelement induced phenotypes.