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Chronic social stress caused by daily agonistic interactions in male mice leads to a mixed anxiety/depression-like disorder that is accompanied by the development of psychogenic immunodeficiency and stimulation of oncogenic processes concurrently with many neurotranscriptomic changes in brain regions. The aim of the study was to identify carcinogenesis- and apoptosis-associated differentially expressed genes (DEGs) in the hypothalamus of male mice with depression-like symptoms and, for comparison, in aggressive male mice with positive social experience. To obtain two groups of animals with the opposite 20-day social experiences, a model of chronic social conflict was used. Analysis of RNA-Seq data revealed similar expression changes for many DEGs between the aggressive and depressed animals in comparison with the control group; however, the number of DEGs was significantly lower in the aggressive than in the depressed mice. It is likely that the observed unidirectional changes in the expression of carcinogenesis- and apoptosis-associated genes in the two experimental groups may be a result of prolonged social stress (of different severity) caused by the agonistic interactions. In addition, 26 DEGs were found that did not change expression in the aggressive animals and could be considered genes promoting carcinogenesis or inhibiting apoptosis. Akt1, Bag6, Foxp4, Mapk3, Mapk8, Nol3, Pdcd10, and Xiap were identified as genes whose expression most strongly correlated with the expression of other DEGs, suggesting that their protein products play a role in coordination of the neurotranscriptomic changes in the hypothalamus. Further research into functions of these genes may be useful for the development of pharmacotherapies for psychosomatic pathologies.

The hippocampus is known as the brain region implicated in visuospatial processes and processes associated with learning and short- and long-term memory. An important functional characteristic of the hippocampus is lifelong neurogenesis. A decrease or increase in adult hippocampal neurogenesis is associated with a wide range of neurological diseases. We have previously shown that in adult male mice with a chronic positive fighting experience in daily agonistic interactions, there is an increase in the proliferation of progenitor neurons and the production of young neurons in the dentate gyrus (in hippocampus), and these neurogenesis parameters remain modified during 2 weeks of deprivation of further fights. The aim of the present work was to identify hippocampal genes associated with neurogenesis and involved in the formation of behavioral features in mice with the chronic experience of wins in aggressive confrontations, as well as during the subsequent 2-week deprivation of agonistic interactions. Hippocampal gene expression profiles were compared among three groups of adult male mice: chronically winning for 20 days in the agonistic interactions, chronically victorious for 20 days followed by the 2-week deprivation of fights, and intact (control) mice. Neurogenesis-associated genes were identified whose transcription levels changed during the social confrontations and in the subsequent period of deprivation of fights. In the experimental males, some of these genes are associated with behavioral traits, including abnormal aggression-related behavior, an abnormal anxiety-related response, and others. Two genes encoding transcription factors (Nr1d1 and Fmr1) were likely to contribute the most to the between-group differences. It can be concluded that the chronic experience of wins in agonistic interactions alters hippocampal levels of transcription of multiple genes in adult male mice. The transcriptome changes get reversed only partially after the 2-week period of deprivation of fights. The identified differentially expressed genes associated with neurogenesis and involved in the control of a behavior/neurological phenotype can be used in further studies to identify targets for therapeutic correction of the neurological disturbances that develop in winners under the conditions of chronic social confrontations.

Background Genome-wide association studies have identified the CDC7-TGFBR3 intergenic region on chromosome 1 to be strongly associated with optic disc area size. The mechanism of its function remained unclear until new data on eQTL markers emerged from the Genotype-Tissue Expression project. The target region was found to contain a strong silencer of the distal (800 kb) Transcription Factor (TF) gene GFI1 (Growth Factor Independent Transcription Repressor 1) specifically in neuroendocrine cells (pituitary gland). GFI1 has also been reported to be involved in the development of sensory neurons and hematopoiesis. Therefore, GFI1, being a developmental gene, is likely to affect optic disc area size by altering the expression of the associated genes via long-range interactions. Results Distribution of haplotypes in the putative enhancer region has been assessed using the data on four continental supergroups generated by the 1000 Genomes Project. The East Asian (EAS) populations were shown to manifest a highly homogenous unimodal haplotype distribution pattern within the region with the major haplotype occurring with the frequency of 0.9. Another European specific haplotype was observed with the frequency of 0.21. The major haplotype appears to be involved in silencing GFI1repressor gene expression, which might be the cause of increased optic disc area characteristic of the EAS populations. The enhancer/eQTL region overlaps AluJo element, which implies that this particular regulatory element is primate-specific and confined to few tissues. Conclusion Population specific distribution of GFI1 enhancer alleles may predispose certain ethnic groups to glaucoma.

The neuromolecular mechanisms forming behavioral pathology developing in male mice in response to repeated experience of aggression and mixed anxiety-depressive disorder due to chronic social stress were studied. These studies tested the suggestion that altered expression of genes of the Slc6a family, which encode monoamine, GABA, taurine, glycine, and other amino acid transporter proteins can be used as an indicator of changes in the operation of the neurotransmitter systems in five parts of the brain involved in the processes forming pathological forms of behavior. The transcriptomes of brain areas in control, aggressive, and depressive mice were sequenced at Genoanalytica (http://genoanalytica.ru/, Moscow, Russia). The analysis results (RNA-Seq) identified different changes in the expression of the transporter genes the Slc6a family depending on brain area, behavioral pathology, and the functions of the protein encoded by the corresponding genes. In particular, increases in the expression of most GABAergic Slc6a genes were seen in the hypothalamus, hippocampus, and striatum in depressive mice and in the hypothalamus of aggressive males. The midbrain raphe nuclei and ventral tegmental area showed specific and opposite changes in the expression of the monoaminergic genes. These data lead to the conclusion that the altered expression of the Slc6a genes, encoding the corresponding transporters, may serve as a marker for changes in the functions of the neurotransmitter systems in pathological states.

Midbrain raphe nuclei (MRNs) contain a large number of serotonergic neurons associated with the regulation of numerous types of psychoemotional states and physiological processes. The aim of this work was to study alterations of the MRN transcriptome in mice with prolonged positive or negative fighting experience and to identify key gene networks associated with the regulation of serotonergic system functioning. Numerous genes underwent alterations of transcription in the MRNs of male mice that either manifested aggression or experienced social defeat in daily agonistic interactions. The expression of the Tph2 gene encoding the rate-limiting enzyme of the serotonin synthesis pathway correlated with the expression of many genes, 31 of which were common between aggressive and defeated mice and were downregulated in the MRNs of mice of both experimental groups. Among these common differentially expressed genes (DEGs), there were genes associated with behavior, learning, memory, and synaptic signaling. These results suggested that, in the MRNs of the mice, the transcriptome changes associated with serotonergic regulation of various processes are similar between the two groups (aggressive and defeated). In the MRNs, more DEGs correlating with Tph2 expression were found in defeated mice than in the winners, which is probably a consequence of deeper Tph2 downregulation in the losers. It was shown for the first time that, in both groups of experimental mice, the changes in the transcription of genes controlling the synthesis and transport of serotonin directly correlate with the expression of genes Crh and Trh, which control the synthesis of corticotrophin- and thyrotropin-releasing hormones. Our findings indicate that CRH and TRH locally produced in MRNs are related to serotonergic regulation of brain processes during a chronic social conflict.

Midbrain raphe nuclei (MRNs) contain a large number of serotonergic neurons associated with the regulation of numerous types of psychoemotional states and physiological processes. The aim of this work was to study alterations of the MRN transcriptome in mice with prolonged positive or negative fighting experience and to identify key gene networks associated with the regulation of serotonergic system functioning. Numerous genes underwent alterations of transcription in the MRNs of male mice that either manifested aggression or experienced social defeat in daily agonistic interactions. The expression of the Tph2 gene encoding the rate-limiting enzyme of the serotonin synthesis pathway correlated with the expression of many genes, 31 of which were common between aggressive and defeated mice and were downregulated in the MRNs of mice of both experimental groups. Among these common differentially expressed genes (DEGs), there were genes associated with behavior, learning, memory, and synaptic signaling. These results suggested that, in the MRNs of the mice, the transcriptome changes associated with serotonergic regulation of various processes are similar between the two groups (aggressive and defeated). In the MRNs, more DEGs correlating with Tph2 expression were found in defeated mice than in the winners, which is probably a consequence of deeper Tph2 downregulation in the losers. It was shown for the first time that, in both groups of experimental mice, the changes in the transcription of genes controlling the synthesis and transport of serotonin directly correlate with the expression of genes Crh and Trh, which control the synthesis of corticotrophin- and thyrotropin-releasing hormones. Our findings indicate that CRH and TRH locally produced in MRNs are related to serotonergic regulation of brain processes during a chronic social conflict.

Long intergenic noncoding RNA (lincRNA) genes are abundant in mammals, but their functions remain elusive. The characteristics of lincRNAs can be studied via comparative analysis with those of mRNAs, for which there is a wealth of information. Highly conserved coding sequences (exons) and the exon–intron structure are some typical evolutionary features attributed to eukaryotic mRNAs. The exon structure is conserved considerably less in lincRNA, but to a greater degree than for introns. Comparative analysis of putative intron positions in lincRNA genes in a range of mammalian genomes underscored the high positional conservation for some introns, which appear to be up to 100 million years old. It is therefore possible that primary and/or secondary structure of these molecules confers functional signals.

Chronic agonistic interactions promote the development of experimental psychopathologies in animals: a depression-like state in chronically defeated mice and the pathology of aggressive behavior in the mice with repeated wins. The abundant research data indicate that such psychopathological states are associated with significant molecular and cellular changes in the brain. This paper aims to study the influence of a 20-day period of agonistic interactions on the expression patterns of collagen family genes encoding the proteins which are basic components of extracellular matrix (ECM) in different brain regions of mice using the RNA-Seq database. Most of differentially expressed collagen genes were shown to be upregulated in the hypothalamus and striatum of chronically aggressive and defeated mice and in the hippocampus of defeated mice, whereas downregulation of collagen genes was demonstrated in the ventral tegmental areas in both experimental groups. Aberrant expression of collagen genes induced by chronic agonistic interactions may be indicative of specific ECM defects in the brain regions of mice with alternative social experience. This is the first study demonstrating remodeling of ECM under the development of experimental disorders.

Background Fat mass and obesity-associated (FTO) gene has been under close investigation since the discovery of its high impact on the obesity status in 2007 by a range of publications. Recent report on its implication in adipocytes underscored its molecular and functional mechanics in pathology. Still, the population specific features of the locus structure have not been approached in detail. Methods We analyzed the population specific haplotype profiles of FTO genomic locus identified by Genome Wide Association Studies (GWAS) for the high obesity risk by examining eighteen 1000G populations from 4 continental groups. The GWAS SNPs cluster is located in the FTO gene intron 1 spanning around 70 kb. Results We reconstructed the ancestral state of the locus, which comprised low-risk major allele found in all populations, and two minor risk-associated alleles, each one specific for African and European populations, correspondingly. The locus structure and its allele frequency distribution underscore the high risk allele frequency specifically for the European population. South Asian populations have the second highest frequency of risk alleles, while East Asian populations have the lowest. African population-specific minor allele was only partially risk-associated. All of the GWAS SNPs considered are manifested by low risk alleles as reference (major) ones (p > 0.5) in each of the continental groups. Strikingly, rs1421085, recently reported as a causal SNP, was found to be monomorphic in ancestral (African) populations, implying possible selection sweep in the course of its rapid fixation, as reported previously. Conclusion The observations underscore varying FTO -linked risk in the manifestation of population specific epidemiology of genetically bound obesity. The results imply that the FTO locus is one of the major genetic determinants for obesity risk from GWAS SNPs set. Electronic supplementary material The online version of this article (10.1186/s12920-019-0491-x) contains supplementary material, which is available to authorized users.

Genome-wide association studies have identified the CDC7-TGFBR3 intergenic region on chromosome 1 to be strongly associated with optic disc area size. The mechanism of its function remained unclear until new data on eQTL markers emerged from the Genotype-Tissue Expression project. The target region was found to contain a strong silencer of the distal (800 kb) Transcription Factor (TF) gene GFI1 (Growth Factor Independent Transcription Repressor 1) specifically in neuroendocrine cells (pituitary gland). GFI1 has also been reported to be involved in the development of sensory neurons and hematopoiesis. Therefore, GFI1, being a developmental gene, is likely to affect optic disc area size by altering the expression of the associated genes via long-range interactions.Distribution of haplotypes in the putative enhancer region has been assessed using the data on four continental supergroups generated by the 1000 Genomes Project. The East Asian (EAS) populations were shown to manifest a highly homogenous unimodal haplotype distribution pattern within the region with the major haplotype occurring with the frequency of 0.9. Another European specific haplotype was observed with the frequency of 0.21. The major haplotype appears to be involved in silencing GFI1repressor gene expression, which might be the cause of increased optic disc area characteristic of the EAS populations. The enhancer/eQTL region overlaps AluJo element, which implies that this particular regulatory element is primate-specific and confined to few tissues.Population specific distribution of GFI1 enhancer alleles may predispose certain ethnic groups to glaucoma.

Daily agonistic interactions of mice are an effective experimental approach to elucidate the molecular mechanisms underlying the excitation of the brain neurons and the formation of alternative social behavior patterns. An RNA-Seq analysis was used to compare the ventral tegmental area (VTA) transcriptome profiles for three groups of male C57BL/6J mice: winners, a group of chronically winning mice, losers, a group of chronically defeated mice, and controls. The data obtained show that both winners and defeated mice experience stress, which however, has a more drastic effect on defeated animals causing more significant changes in the levels of gene transcription. Four genes (Nrgn, Ercc2, Otx2, and Six3) changed their VTA expression profiles in opposite directions in winners and defeated mice. It was first shown that Nrgn (neurogranin) expression was highly correlated with the expression of the genes involved in dopamine synthesis and transport (Th, Ddc, Slc6a3, and Drd2) in the VTA of defeated mice but not in winners. The obtained network of 31 coregulated genes, encoding proteins associated with nervous system development (including 24 genes associated with the generation of neurons), may be potentially useful for studying their role in the VTA dopaminergic neurons maturation under the influence of social stress.

The analysis of mtDNA polymorphism was carried out in the population of Siberian Tatars from the Barabinsk forest steppe living on the territory of Novosibirsk oblast (N = 199). As a result of the analysis of HVS I and HVS II nucleotide sequence, 101 haplotypes that refer to 22 mtDNA haplogroups were detected. The population of Baraba Tatars is represented by both East Eurasian (38.7%) and West Eurasian mtDNA lines (61.3%). H, T, U5, and J haplogroups prevail among West Eurasian haplogroups; C, D, G, M, and A haplogroups prevail among East Eurasian ones. According to the index of genetic diversity, Tatars from the Barabinsk forest steppe (0.9141) are the closest to Kazakhs (0.9108), Bashkirs (0.9165), and Tobol-Irtysh Tatars (0.9104). The greatest statistically significant interpopulation differences (FST) were detected between all studied samples; the smallest interpopulation differences were detected between all Tatar samples, as well as between Tatars and Komi, Mansi, Udmurts, Kazakhs, Chuvashes, and Bashkirs. The haplogroup H is the most common in populations that we studied. In the present study, was registered the haplotype 16126–16294 with the frequency of 4% (T cluster) previously found only in Caucasians. High frequency of haplogroups U4, U5, and H in the gene pool of Baraba Tatars brings them together not only with Samoyeds but also with Finno-Ugric populations. The highest intrapopulation genetic diversity was detected in Tatars from the Barabinsk forest steppe, Tobol-Irtysh Tatars, Kazakhs, and Bashkirs. The presence of the haplogroup B in the mitochondrial DNA genetic pool of Siberian Tatars brings them together with Turks that came from regions of Altai and Central Kazakhstan and inhabited the Western Siberian forest steppe in the 6th–9th centuries. The haplogroup U7, which is typical of populations of Jordan, Kuwait, Iran, and Saudi Arabia, could also have entered the territory of residence of Siberian Tatars in the middle of second millennium BC, when Iranian-speaking tribes entered Siberia.

Genotyping of TRPV1 and TRPA1 genes encoding thermoreceptors in the populations of the Altai-Sayan region and the Far East was conducted. The sample consisted of 15 populations comprising 1482 individuals. The analysis of TRPV1 rs222747 demonstrated that the frequency of M315I was closest to East Asian populations only in Nanais and Koryaks (56 and 64%, respectively). Siberian Tatars, Yakuts, and Evenks were closest to European populations. All populations of the Altai-Sayan region reported an intermediate position between the Caucasoids and the Eastern Mongoloids on the basis of the frequency of M315I. No deviations from the Hardy–Weinberg distribution were observed. The observed heterozygosity exceeded the expected one in eight populations. The analysis of TRPA1 rs13268757 revealed that Chukchi, Yukaghir, Koryak, Tuvinian, Southern Altaian, and Telengit populations were closest to the East Asian populations on the basis of the frequency of R3C substitution (3–7%). At the same time, populations of Siberian Tatars, Nanais, Evenks, Yakuts, Shorians, Khakases, and Kazakhs were intermediate between the Caucasoids (18–23%) and the Mongoloids from East Asia (3–7%) on the basis of the frequency of this polymorphism. A deviation from the Hardy–Weinberg distribution was detected only in the Yukaghir population. The observed heterozygosity was higher than the expected one in nine populations. A trans-association of TRPA1 and TRPV1 gene polymorphisms was carried out in 14 populations via regression analysis. A negative correlation of–0.545 was determined, the number of degrees of freedom (df) was 13, and the P-value was 0.048. The data obtained indicate that the analyzed polymorphisms are correlated, which confirms an earlier conclusion of the TRPA1-dependent inhibition of TRPV1 function. The results may evidence in the co-evolution of analyzed genes.

Работа была частично поддержана Министерством образования и науки РФ (28.12487.2018/12.1), разработка базы данных поддержана бюджетным проектом ИЦиГ СО РАН (№ 0324-2018-0019)

A range of several psychiatric medications targeting the activity of solute carrier (SLC) transporters have proved effective for treatment. Therefore, further research is needed to elucidate the expression profiles of the Slc genes, which may serve as markers of altered brain metabolic processes and neurotransmitter activities in psychoneurological disorders. We studied the Slc differentially expressed genes (DEGs) using transcriptomic profiles in the ventral tegmental area (VTA), nucleus accumbens (NAcc), and prefrontal cortex (PFC) of control and aggressive male mice with psychosis-like behavior induced by repeated experience of aggression accompanied with wins in daily agonistic interactions. The majority of the Slc DEGs were shown to have brain region-specific expression profiles. Most of these genes in the VTA and NAcc (12 of 17 and 25 of 26, respectively) were downregulated, which was not the case in the PFC (6 and 5, up- and downregulated, respectively). In the VTA and NAcc, altered expression was observed for the genes encoding the transporters of neurotransmitters as well as inorganic and organic ions, amino acids, metals, glucose, etc. This indicates an alteration in transport functions for many substrates, which can lead to the downregulation or even disruption of cellular and neurotransmitter processes in the VTA and NAcc, which are attributable to chronic stimulation of the reward systems induced by positive fighting experience. There is not a single Slc DEG common to all three brain regions. Our findings show that in male mice with repeated experience of aggression, altered activity of neurotransmitter systems leads to a restructuring of metabolic and neurotransmitter processes in a way specific for each brain region. We assume that the scoring of Slc DEGs by the largest instances of significant expression co-variation with other genes may outline a candidate for new prognostic drug targets. Thus, we propose that the Slc genes set may be treated as a sensitive genes marker scaffold in brain RNA-Seq studies.

CG-rich islands (CpG islands or CGI) are important functional elements in the genome of vertebrates. In particular, they (a) initiate transcription—bidirectional in some cases, due to the self-complementarity of the CG dinucleotides—as promoters in most (>50%) genes of vertebrates; (b) form a global methylation landscape; and (c) act to “switch-off” transcription via methylation. The degenerate nature of CpG islands (elevated CG content) implies an increase in the probability of tandem repeats and palindromes within a CpG island. In this work, tandem duplications of complete CpG islands (megamonomers with a length of 400–5000 bp) are identified in the human genome. We have found both intergenic and intragenic tandem duplications of CpG islands. The discovered CGI duplications are mediated through CG-rich subcentromeric and telomeric satellites and SINEs. The similarity of the monomers in tandem repeats in some cases suggests the existence of selection pressure on the structure of such loci. The context of intergenic tandem CGI repeats indicates their potential role in leveling the CG composition in the genome segment. The found tandem CGIs are transcriptionally active in a wide range of tissues and cell lines. The considered phenomenon of CGI cluster organization is most pronounced in chromosome 19, known for abundant segment duplications and gene expansions. The DXZ4 megasatellite, which resides in the long (q) arm of chromosome X, also belonging to the CGIs generated by tandem duplications, is another unique genome segment.

Xiongnu was a confederation of nomadic pastoral tribes (~200 bc–100 ad) that founded the first nomadic empire in Central Asia. According to archeological and historical data, the tribes played a key role in ethnic and cultural processes in Central Asia and adjacent regions of Eurasia. Genetic studies of the Xiongnu published to date have focused on remains from burial grounds in present-day Mongolia, in the southern part of the ancient Xiongnu area. However, paleoanthropological materials from numerous Xiongnu cemeteries and settlements in Transbaikalia (the southern region of Eastern Siberia, Russia) in the northern part of the Xiongnu Empire have not been examined genetically. Here, we analyzed mitochondrial DNA variation in a Transbaikalian Xiongnu population based on ancient DNA obtained from skeletal remains (n = 18) at four burial grounds to complement available Xiongnu genetic diversity data. We detected 16 mitochondrial DNA haplotypes belonging to seven East Eurasian haplogroups (A, B5, C, D4, G2a, N9a, and Y) in the Transbaikalian Xiongnu series. We observed substantial similarity between Transbaikalian and Mongolian Xiongnu series with respect to main haplogroup composition and frequencies. We observed several mitochondrial DNA clusters (N9a, Y, B5, and A16) and 11 of 16 haplotypes that were previously undetected in the Xiongnu gene pool. We also observed high similarity between the Xiongnu and contemporary indigenous populations of eastern Central Asia, particularly Mongolian-speaking groups. These findings extend our knowledge of Xiongnu genetic diversity.

Profiles of alternative mRNA isoforms have been determined in three brain regions of rats from an aggressive and a tame line selected for 74 generations. Among 2319 genes with alternatively spliced exons, approximately 84% were confirmed by analyzing public databases. Based on Gene Ontology-guided clustering of alternatively spliced genes, it has been found that the sample was enriched in synapse-specific genes (FDR < 10^(-17)). Patterns of gene expression in the brains of animals with genetically determined high or low aggression were more frequently found to differ in the use of alternatively spliced exons than in animals environmentally conditioned for increased or lowered propensity to aggression. For the Adcyap1r1 gene, five alternatively spliced mRNA isoforms have been represented differentially in aggressive animals. A detailed analysis of the gene that encodes glutamate ionotropic receptor NMDA type subunit 1 (Grin1) has confirmed significant differences in the levels of its alternatively spliced isoforms in certain brain regions of tame and aggressive rats. These differences may affect the behavior in rats genetically selected for aggression levels.

Background Medium spiny neurons (MSNs) comprise the main body (95% in mouse) of the dorsal striatum neurons and represent dopaminoceptive GABAergic neurons. The cAMP (cyclic Adenosine MonoPhosphate)—mediated cascade of excitation and inhibition responses observed in MSN intracellular signal transduction is crucial for neuroscience research due to its involvement in the motor and behavioral functions. In particular, all types of addictions are related to MSNs. Shedding the light on the mechanics of the above-mentioned cascade is of primary importance for this research domain. Results A mouse model of chronic social conflicts in daily agonistic interactions was used to analyze dorsal striatum neurons genes implicated in cAMP-mediated phosphorylation activation pathways specific for MSNs. Based on expression correlation analysis, we succeeded in dissecting Drd1- and Drd2-dopaminoceptive neurons (D1 and D2, correspondingly) gene pathways. We also found that D1 neurons genes clustering are split into two oppositely correlated states, passive and active ones, the latter apparently corresponding to D1 firing stage upon protein kinase A (PKA) activation. We observed that under defeat stress in chronic social conflicts the loser mice manifest overall depression of dopamine-mediated MSNs activity resulting in previously reported reduced motor activity, while the aggressive mice with positive fighting experience (aggressive mice) feature an increase in both D1-active phase and D2 MSNs genes expression leading to hyperactive behavior pattern corresponded by us before. Based on the alternative transcript isoforms expression analysis, it was assumed that many genes (Drd1, Adora1, Pde10, Ppp1r1b, Gnal), specifically those in D1 neurons, apparently remain transcriptionally repressed via the reversible mechanism of promoter CpG island silencing, resulting in alternative promoter usage following profound reduction in their expression rate. Conclusion Based on the animal stress model dorsal striatum pooled tissue RNA-Seq data restricted to cAMP related genes subset we elucidated MSNs steady states exhaustive projection for the first time. We correspond the existence of D1 active state not explicitly outlined before, and connected with dynamic dopamine neurotransmission cycles. Consequently, we were also able to indicate an oscillated postsynaptic dopamine vs glutamate action pattern in the course of the neurotransmission cycles.

Cancer genomes accumulate nucleotide sequence variations that number in the tens of thousands per genome. A prominent fraction of these mutations is thought to arise as a consequence of the off-target activity of DNA/RNA editing cytosine deaminases. These enzymes, collectively called activation induced deaminase (AID)/APOBECs, deaminate cytosines located within defined DNA sequence contexts. The resulting changes of the original C:G pair in these contexts (mutational signatures) provide indirect evidence for the participation of specific cytosine deaminases in a given cancer type. The conventional method used for the analysis of mutable motifs is the consensus approach. Here, for the first time, we have adopted the frequently used weight matrix (sequence profile) approach for the analysis of mutagenesis and provide evidence for this method being a more precise descriptor of mutations than the sequence consensus approach. We confirm that while mutational footprints of APOBEC1, APOBEC3A, APOBEC3B, and APOBEC3G are prominent in many cancers, mutable motifs characteristic of the action of the humoral immune response somatic hypermutation enzyme, AID, are the most widespread feature of somatic mutation spectra attributable to deaminases in cancer genomes. Overall, the weight matrix approach reveals that somatic mutations are significantly associated with at least one AID/APOBEC mutable motif in all studied cancers.

Genetic predisposition to tick-borne encephalitis (TBE) is rather poorly studied in human populations. Human genes encoding crucial components of antiviral immune response are most likely involved in protective mechanisms against TBE virus. Previously, several single nucleotide polymorphisms (SNPs) located in interleukin 28B (IL28B) and interleukin 10 (IL10) genes were associated with predisposition to chronic hepatitis C (caused by a structurally similar virus from the same Flaviviridae family) in a number of human populations. The aim of the present study was to estimate a possible association of the IL28B gene rs8103142 and rs12980275 SNPs and IL10 gene rs1800872, rs3021094, and rs3024498 SNPs with predisposition to TBE in a Russian population. Genotypic and allelic frequencies for these SNPs were analyzed in 132 non-immunized TBE patients (34 with fever, 60 with meningitis, and 38 with severe central nervous system disease) and compared with the population control (221 Novosibirsk citizens). The results obtained suggest that both studied IL28B gene SNPs, as well as the IL10 gene rs1800872 SNP are associated with predisposition to TBE in Russian population.

The human TRPM8 gene encodes a receptor mediating cold sensitivity, and this points to its putative role in cold adaptation. The structural variability of the TRPM8 gene for five single-nucleotide polymorphisms (SNPs) has been studied in the Kyrgyz population. The SNPs are located in the coding regions of the gene, and three of them are confined to a 20-bp segment in exon 7. The frequencies of minor SNP alleles are as follows: rs13004520 G/C = 0.06; rs28901637 A/T = 0.13; rs11562975 G/C = 0.27; rs7593557 G/A = 0.21; rs11563071 C/G = 0.12. The analyzed sample of Kyrgyz population includes 275 individuals living at different altitudes and under drastically different climatic conditions. The frequency of the minor rs11562975 allele in the highlanders (living above 3200 m ASL and higher) is lower by a factor of 1.5 than in the residents of lower regions (760–3000 m ASL; p < 0.01). This result indicates a selective role of rs11562975 in adapting to cold. A comparison of haplotype frequencies in the Kyrgyz population with Europeans, East Asians, and Africans shows a clear narrowing of genotype variation in Europeans in comparison to all the others. Probably, this phenomenon is related to a decline in the population size (bottleneck effect) during evolution. We consider the exon–intron structure of the TRPM8 gene. The epigenetic markers in the vicinity of the gene have been analyzed. Two strong binding sites for insulator ctcf proteins are present there. They are likely to be associated with chromatin conformation and alternative splicing regulation. A structural–functional characterization of genes for the TRP protein family is provided.

The DC-SIGN (dendritic cell-specific intercellular adhesion molecule (ICAM)-3-grabbing non-integrin) and TLR3 (toll-like receptor 3) proteins are key effectors of the innate immunity and particularly play an important role in the organism’s antiviral defense as pattern-recognition receptors. Previously, we demonstrated that certain genotypes and alleles of single nucleotide polymorphisms (SNPs) rs2287886 (G/A) in the promoter region of the CD209 gene (encoding DC-SIGN) and rs3775291 (G/A, Leu412Phe) in the exon 4 of the TLR3 gene are associated with human predisposition to tick-borne encephalitis in the Russian population. In the present work, the distribution of genotype and allele frequencies for these SNPs was studied in seven populations of North Eurasia, including Caucasians (Russians and Germans (from Altai region)), Central Asian Mongoloids (Altaians, Khakass, Tuvinians, and Shorians), and Arctic Mongoloids (Chukchi). It was found that the CD209 gene rs2287886 SNP A/A genotype and A allele, as well as the TLR3 gene rs3775291 SNP G/G genotype and G allele (the frequencies of which in our previous studies were increased in tick-borne encephalitis patients as compared with the population control (Russian citizens of Novosibirsk)), are preserved with a high frequency in Central Asian Mongoloids (who for a long time regularly came in contact with tick-borne encephalitis virus in places of their habitation). We suggested that predisposition to tick-borne encephalitis in Central Asian Mongoloid populations can be predetermined by a different set of genes and their polymorphisms than in the Russian population.

Old Believers of the Tyumen oblast have been studied compared with a control sample of Russian residents of the city of Novosibirsk. The former are a unique subpopulation, which has been relatively isolated from the rest of Russians in central and northern regions of Russia due to religious reasons since the middle of the 17th century. Polymorphisms in the genes for glycoprotein ITGB3, dopamine-β-hydroxylase (DBH), and chemokine receptor CCR2 and two mutations in the c-fms gene have been analyzed. The populations are only similar in the c-fms indel. The frequencies of the rare alleles of CCR2, ITGB3, and 3'UTR of c-fms in the Old Believers are lower than in the sample of Novosibirsk Russians, and the rare allele of DBH is more frequent. A significant negative correlation is observed between DBH and CCR2 (r =–0.88; df = 4; P < 0.023). Apparently, these differences are related to the long-term isolation of Old Believers. This assumption is consistent with the fact that the levels of heterozygosity for most loci in Old Believers are lower than in Novosibirsk Russians.

The mtDNA polymorphism in representatives of various archaeological cultures of the Developed Bronze Age, Early Scythian, and Hunnish-Sarmatian periods was analyzed (N = 34). It detected the dominance of Western-Eurasian haplotypes (70.6%) in mtDNA samples from the representatives of the ancient population of the Early Bronze Age--Iron Age on the territory of Altai Mountains. Since the 8th to the 7th centuries BC, a sharp increase was revealed in the Eastern-Eurasian haplogroups A, D, C, andZ (43.75%) as compared to previous cultures (16.7%). The presence of haplotype 223-242-290-319 of haplogroup A8 in Dolgans, Itelmens, Evens, Koryaks, and Yakuts indicates the possible long-term presence of its carriers in areas inhabited by these populations. The prevalence of Western-Eurasian haplotypes is observed not only in the Altai Mountains but also in Central Asia (Kazakhstan) and the South of the Krasnoyarsk Krai. All of the three studied samples from the Western-Eurasian haplogroups were revealed to contain U, H, T, and HV. The ubiquitous presence of haplotypes of haplogroup H and some haplogroups of cluster U (U5al, U4, U2e, and K) in the vast territory from the Yenisei River basin to the Atlantic Ocean may indicate the direction of human settlement, which most likely occurred in the Paleolithic Period from Central Asia.

The Leishmania donovani species complex consists of all L. donovani and L. infantum strains mainly responsible for visceral leishmaniasis (VL). It was suggested that genome rearrangements in Leishmania spp. occur very often, thus enabling parasites to adapt to the different environmental conditions. Some of these rearrangements may be directly linked to the virulence or explain the reduced efficacy of antimonial drugs in some isolates. In the current study, we focused on a large-scale analysis of putative gene conversion events using publicly available datasets. Previous population study of L. donovani suggested that population variability of L. donovani is relatively low, however the authors used masking procedures and strict read selection criteria. We decided to re-analyze DNA-seq data without masking sequences, because we were interested in the most dynamic fraction of the genome. The majority of samples have an excess of putative gene conversion/recombination events in the noncoding regions, however we found an overall excess of putative intrachromosomal gene conversion/recombination in the protein coding genes, compared to putative interchromosomal gene conversion/recombination events.

Modes of evolution of stop codons in protein-coding genes, especially the conservation of UAA, have been debated for many years. We reconstructed the evolution of stop codons in 40 groups of closely related prokaryotic and eukaryotic genomes. The results indicate that the UAA codons are maintained by purifying selection in all domains of life. In contrast, positive selection appears to drive switches from UAG to other stop codons in prokaryotes but not in eukaryotes. Changes in stop codons are significantly associated with increased substitution frequency immediately downstream of the stop. These positions are otherwise more strongly conserved in evolution compared to sites farther downstream, suggesting that such substitutions are compensatory. Although GC content has a major impact on stop codon frequencies, its contribution to the decreased frequency of UAA differs between bacteria and archaea, presumably, due to differences in their translation termination mechanisms.