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The regulatory protein encoded by the rosR gene is involved in the processes of adaptation of root nodule bacteria Rhizobium leguminosarum to changes in environmental conditions. It affects the expression of a number of genes associated with the synthesis of exopolysaccharides, which play a critical role in formation of bacterial biofilms on various surfaces. The goal of this work was to study the effect of overexpression of the rosR gene on formation of R. leguminosarum biofilms on inert surfaces and roots of heterologous plant hosts by obtaining recombinant strains with an additional copy of the rosR gene under the control of the Pm promoter. Our analysis of recombinant strains showed that additional expressed copies of the rosR gene allowed rhizobia to overcome the inhibitory effect on biofilm formation caused by low calcium concentrations in the medium, the effect of proteases and detergents, and to form biofilms more efficiently on the surface of tomato and clover roots. The results obtained open up prospects for using rosR as a tool both for increasing the efficiency of endosymbiosis of rhizobia with legumes, and for the formation of stable associative interactions with other agricultural crops.

The emergence of the new SARS-CoV-2 coronavirus has given rise to many enigmas, to which there are no answers yet. However, the degree of threat to humanity, due to the fact that by the beginning of February 2021, more than 100 million people were ill in the world, of which 2 million died, led to the fact that the efforts of many researchers were aimed at combating this disease, including massive sequencing of the complete genomes of SARS-CoV-2, as this is necessary for diagnostics and prediction of the epidemiological situation, including in the long term. Currently, a fairly high level of conservativeness of the SARS-CoV-2 genome is shown, but there is also a significant variability of intra-host viral RNA, confirming the concept of the existence of quasispecies for RNA-containing viruses. As of February 2021, the complete genomes of almost half a million coronavirus isolates have been sequenced worldwide, and a number of nomenclatures have been proposed to streamline their analysis, including the convenient dynamic nomenclature Pango lineage. Variations of SARS-CoV-2 genomes in the form of consensus SNPs (Single Nucleotide Polymorphism) and intra-host iSNVs (intra-host Single Nucleotide Variant) were demonstrated. Taking into account iSNV and minor mutations, about 85% of the 29.9 thousand nucleotides viral genome were changed at least once, but only a very few of them turned into major mutations due to certain features that ensure the predominant distribution of such strains. The example of the S-protein gene, taking into account iSNV, minor and major mutations, shows its significant variability, which is detected when sequencing hundreds of thousands of SARS-CoV-2 genomes. On the basis of the analysis of 400 complete SARS-CoV-2 genomes isolated on the territory of the Russian Federation during 2020, the dynamics of the circulation of individual strains with acquired major mutations, the representation of which is slightly different from the changes in the SARS-CoV-2 genome in the rest world, is estimated. The possibility of long-term persistence of the new coronavirus in the human body is note, while the reservoirs for the latent existence of SARS-CoV-2, in contrast, for example, to the herpes simple virus, remain unknown. There is no consensus on the possibility of reactivation of SARS-CoV-2 or reinfection. The latter is theoretically possible in cases where SARS-CoV-2 strains belonging to other genetic lineages and clades are found in the body of the "re-infected". This, however, does not exclude the possibility of mutating the virus within a single host. Despite significant progress in monitoring the spread of SARS-CoV-2, many questions remain, but as knowledge of the biology of the new coronavirus accumulates, they will also be answered.

Steroid hormone 20-hydroxyecdysone (20E) initiates larval molting start and metamorphosis and regulates reproduction. Its basic receptor is heterodimer including proteins EcR and USP. Ecdysone receptor gene EcR coding protein EcR is a key regulatory element of gene circuits cover considerable part of genes, implicated in growth and development as well as in reproduction of progeny and reactions of organisms to unfavorable factors of environment. The source of methyl groups S-adenosylmethionine (SAM) is in use for biosynthesis of juvenile hormone (JH), methylation of histone proteins and DNA. The main aim of our investigation was evaluation of transcriptional activity of housefly Musca domestica ecdysone receptor gene EcR under adding into ration of 20E and SAM in non-lethal concentrations. Experiments were carried out with larvae and adults of housefly from laboratory strains Shgen and Lgen differ in life span of adults. Change of gene EcR transcripts content in common pool of mRNA in the cells of muscles and gonads, as well as DNA methylation level in 5’-terminal site registered by quantitative real time PCR (RT-PCR). The results of our investigations allow us to suggest existence of mechanism for regulating expression of the EcR gene in M. domestica which is sensitive to exogenic20E and heat stress action as well as to presence of SAM in food. Variations in the mRNA quantitative ratios of EcR gene 5’-and 3’-terminal regions depending on tissue type, gender and age support the hypothesis that this gene can encode several isoforms of the protein EcR. The detected changes in the status of DNA methylation in the 5'-terminal region of the gene and fluctuations in the representation of different mRNA sites after SAM processing suggest the involvement of DNA methylation/demethylation processes in the regulation of EcR gene expression in M. domestica.

The paper considers the problematic aspects of detecting a new coronavirus infection using RT-PCR, which often lead to false negative diagnostic results, which occur both at the preanalytic stage and during nucleic acid amplification, including the interpretation of the obtained data. The viral load in humans was evaluated and assumptions were made about the expected number of viral particles in the studied oropharyngeal and nasopharyngeal samples. The list of diagnostic test systems approved for use in the Russian Federation for detecting SARS-CoV-2 with their brief characteristics is given. The necessity of simultaneous use of several targets in the coronavirus genome in one test system detected by probes with the same fluorochrome is noted, which on the one hand increases the probability of detection by increasing the signal, and on the other hand eliminates the false negative results that could occur in the case of mutations in the virus genome at the sites of annealing primers and hybridization probes.

Transgenic plants Nicotiana tabacum, Brassica napus, B. rapa, Eruca sativa with target gene AtGSTF11 were created. Their stress resistance is being studied.

In the set of experiments with short-living and long-living housefly strains Sh gen and L gen we showed that starvation as restriction of food availability for young adults at reproductive maturation stage caused change of life span and fecundity in parent generation and consecutive offspring generations. Change of viability and developmental time of progeny demonstrated transgenerational nature of starvation stress.

Plant infection with Agrobacterium rhizogenes leads to the development of a hairy root disease notable for the rapid agravitropic growth of roots on hormone-free nutrient media. In order to look into the interaction of A. rhizogenes with plants and assess opportunities of practical application of hairy root culture, new approaches to their production are elaborated. A method of bacterium-free and plasmid-free production of genetically modified roots (hairy roots) by means of biolistic transformation of leaf explants with a DNA fragment (size of 5461 bp) consisting of genes rolA, rolB, rolC, and rolD are proposed. In most cases, such transformation resulted in the emergence of only adventitious roots with transient expression of rol-genes, and the growth of such roots on hormone-free media ceased in 2–3 months in contrast to genuine hairy roots capable of unrestricted growth. Molecular analysis of different systems of target genes’ expression showed an important role of transgene rolC and host gene of cyclin-dependent protein kinase CDKB1-1 in the maintenance of rapid growth of hairy roots in vitro (in isolated cultures).

The expression level of the gene PtrXTH1 encoding xyloglucan endo-transglycosylase in the leaves of Populus tremula L. of wild-type and in response to exogenous phytohormones treatment was analyzed. The highest level of transcripts of PtrXTH1 was detected in young, intensively growing leaves of aspen. In young aspen leaves, the expression of PtrXTH1 was induced by cytokinins, auxins, and brassinosteroids. The content of PtrXTH1 transcripts increased under the constitutive expression of the PnARGOS-LIKE gene. Bioinformatic analysis of PtXTH1 putative promoter region in P. trichocarpa Torr. and A. Gray ex. Hook showed the presence of cis-regulatory elements associated with the regulation of growth and stress resistance. To determine the role of the gene under study, we also created transgenic tobacco plants with constitutive expression of the PnXTH1 gene (the ortholog of PtrXTH1 from the black poplar P. nigra). Transgenic tobacco plants were characterized by an increase in leaf size and fresh and dry weight of the aboveground part under normal growth conditions. When grown under conditions of salinization and drought, transgenic plants were distinguished by increased stress resistance due to the maintenance of cell expansion in roots and stems at a higher level and the ability to more effectively retain water in leaves compared with wild-type plants.

The transcription activity of genes involved in diapause regulation in Colorado potato beetle adults in diapause preparation and in the middle of winter is studied under laboratory conditions. The gonads of beetles remaining active, unlike those of the dormant ones, contain mRNA for the Rdl subunit of the gamma aminobutyric acid (GABA)A receptor. In the middle of winter diapause, the muscle and gonad tissues of beetles exposed to fipronil, a noncompetitive inhibitor of the GABAA-gated ionotropic channels, contain elevated amounts of mRNAs of the DP1, fer, DAT1, DAT2, EcR, and Ldace-1 genes. It is presumed that fipronil considerably influences the regulatory processes occurring in diapause development by blocking the GABA–GABA-receptor binding.

Transgenic tobacco plants expressing Arabidopsis thaliana ARGOS and ARGOS-LIKE genes under the control of the chalcone synthase promoter of Petunia hybrida L., as well as the estradiol inducible XVE system, have been obtained. The part of transgenic plants with flower-specific expression of the target genes was characterized by increased flower size, caused by an increase in cell size and quantity in the case of the ARGOS gene and by a stimulation of cell growth via stretching in the case of the ARGOS-LIKE gene. An enhanced expression level of the NtEXPA1, NtEXPA4 genes encoding expansins, NtEXGT gene encoding endo-xyloglucan transferase, and the AINTEGUMENTA-like gene was detected in the flowers of transgenic tobacco plants. In the case of inducible expression of ARGOS and ARGOS-LIKE genes, an increase in leaf, stem and flower size was revealed in several lines of transgenic plants as compared to control. Expression of the ARGOS gene also affected cell number and size in this case, while the ARGOS-LIKE gene mainly influenced cell size via stretching. Inducible expression of the ARGOS gene in flowers mainly provided an enhanced containment of AINTEGUMENTA-like mRNA, while ARGOS-LIKE gene expression resulted in the activation of NtEXPA1 and NtEXGT genes.

Assortative mating and hypervariability as the result of genomic stress, caused by selection, appear the main components of the mechanism of intrapopulation polymorphism maintenance. Activation of genome transposable elements has contributed significantly to increasing of variability provoked by inbreeding. Copy number of transposone Hermes DNA evaluation in somatic tissues of Musca domestica individuals from the strains differ by the life span at all developmental stages used as the criterion of genome stability. Investigations funded by RFBR 12-04-01450-a and 11-04-97005-r_povolzhje_a.

Speciation as a micro-evolutionary process begins with emerging of intraspecies differentiation, which is associated with establishment of reproductive isolation. One of intrinsic isolation factors ensuring physiological isolation is assortative mating. In course of long-term field observations in the Southern Urals (Republic of Bashkortostan) and prolonged laboratory experiments, we have detected assortative mating in populations of potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae). Three morphotypes were singled out by the extent of integument melanization, namely achromists (A), melanists (M), and intermediate type (I), and frequency of occurrence of these morphotypes imago pairs significantly deviated from random distribution, thus manifesting the assortative mating. Under in copulo conditions, mating between achromist males (A) and melanist females (M) where active choice belonged to males was not registered. In.laboratory experiments, in the sample of 40 artificially formed pairs, there were detected significant differences in longevity and fecundity of different morphotype imagoes. Achromists and melanists had significantly (almost two times) higher longevity as compared with intermediate type. Females of intermediate type were significantly more fecund in homonomous crossings than achromists and melanists. It is shown that pairs offspring also differs significantly in viability, with highest viability being characteristic for offspring from females of A- and I-type. The differences revealed are indicative of different reproductive strategies that exist in populations. In laboratory line S of house fly Musca domestica L. (Diptera: Muscidae) the presence of individuals with different reproductive strategies related to longevity is detected. Maximum longevity in inbred lines Sh28 (short living) and L2 (long living), isolated from the line S, significantly differed almost twofold. In the line of short living flies, mass reproduction occurs on the first-second week of imago stage, while in long living flies it is put off to the third-fourth week. In reciprocal crossings between the lines, drastic reduction in females fecundity is observed as well as reduction in viability of females from hybrid offspring. The results obtained are indicative of substantial role of assortative mating and frequency-dependent selection in maintenance of intrapopulation diversity.

New approaches to the detection of impaired nucleotides based on the allele specific ligation of a "C probe" followed by rolling circle amplification have been developed. The detection of amplification products was realized by using enzymatic and deoxyribozyme digestion of fluorescently-labeled DNA-RNA-DNA chimeric oligonucleotide structures in cycling probe technology (CPT) in real-time mode.

M129V polymorphism of prion protein gene PRNP has been studied in patients with multiple sclerosis (MS) and healthy ethnic Russians from Bashkortostan using allele-specific PCR. The genotype frequency distribution of the examined polymorphism in Russians from Bashkortostan was similar to that in European populations. MM, MV, and VV genotype frequencies in control group and in the MS patients were 50.24%, 42.58%, 7.18% and 43.33%, 45.83%, 10.84%, respectively. It was shown that in the group of MS patients with onset of the disease at the age of 21 and older, the frequency of the VV genotype was higher than in the control group (14.3% versus 6.18%, respectively, P = 0.041). We suggest that the VV genotype is associated with higher risk factor of MS development in the patients aged 21 years and older.

The process of accumulation of knowledge on wheat and related wild species during the 20th century is briefly reviewed with special reference to the evidence of the recent years on evolution of polyploid wheats and the role of diploid species. The latter serve as potential donors of the genomes, detection of which is particularly important because of the continuing speciation in the tribe Triticeae and artificial development of synthetic forms. The arguments in favor of the donor role for various diploid wheat and aegilops species from the section Sitopsis are compared. It is stated that in the formation of the both lines of polyploid wheats turgidum–aestivumand timopheevi,diploid Aegilops speltoides acted as a maternal form. In addition to cytoplasmic genomes, this aegilops species introduced into them also the B and G nuclear subgenomes. A comparison of nucleotide sequences in the variable part of the promoter of evolutionary conserved rRNA genes in polyploid wheats with their counterparts in diploid wheats and aegilops species confirmed the accepted wheat phylogenies.