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In conditions of vegetative trial carried out against selective backgrounds in 2017-2019 the response of 27 flax samples to a decrease in soil acidity to neutral pHKCl was studied. The scheme of the experiment was as follows: variant I (control) − pHKCl 5.3-5.5, P2O5 − 320-340 mg/kg, K2O − 81-92 mg/kg; variant II − pHKCl 6.2, P2O5 − 312-345 mg/kg, K2O − 84-98 mg/kg. It has been shown that during the «herringbone» phase in the majority of studied flax genotypes against the background of pH 6.2, the symptoms of “physiological oppression” of flax were observed: small spots developed on the upper leaves, the plants stopped growing, the stems thickened, and the tops of severely affected plants died off. As a result, at the beginning of the growing season at plant height of 7-10 cm, most of the samples were severely affected (from 69 to 100 %). The exceptions were varieties of fibre-flax Hermes (France), Vega 2 (Lithuania), Atlant (Russia) and linseed genotypes No. 3896 (Russia) and Norlin (Canada), which had a weak and medium degree of affection (8.3-45.5 %). Moreover, these genotypes showed a high level of both biological (75-90 %) and agronomic (77.3-85.6 %) resistance in the phase of "early yellow ripeness". The identified flax collection samples can be used as sources of resistance to flax «physiological oppression» caused by stressful edaphic factors in a neutral environment. On the basis of the analysis of the main elements of fiber productivity in studied flax genotypes, it has been established that against the background of pH 6.2 the reduce in plant height was from 11.4 to 52.1 % relative to the control, weight of the technical part of the stem − from 7.2 to 83.4 % , fiber mass − from 9.6 to 85.1 %. For the first time, on the basis of hybridological analysis, an assumption was done as to the pres-ence of a strong dominant gene, controlling the resistance to high soil pH values in the Hermes (France) flax variety and the linseed line No. 3896 (Russia).

To assess the current state of phytoplankton in the littoral area of Lake Baikal and provide a baseline for future comparisons, we sampled spring plankton communities from the 44 littoral and 3 pelagic stations covering all three basins of the lake. The study examined chemical parameters of water (NH4+, NO2−, NO3−, PO4−3, Si, COD), species composition, abundance, and biomass of phytoplankton in Lake Baikal during late spring 2017. Sharp spatial heterogeneity was observed in the distribution of phytoplankton biomass along the western (399 ± 72 mg/m3) and eastern (1319 ± 220 mg/m3) shores of the lake. The phytoplankton were diverse, with 79 species; dominant algae were different from site to site and from south to north throughout the lake. In Southern and Central Baikal, we recorded an intense bloom of the diatom Synedra acus subsp. radians (28–1400 cells/mL), similar to that observed for the past 10 years, while the chrysophyte Dinobryon cylindricum dominated in Northern Baikal. The diatoms Aulacoseira baicalensis, A. islandica, and Stephanodiscus meyeri that were dominant in the 1960s–1990s were not numerous in 2017 (0.5–10 cells/mL). This change in dominant species indicates structural changes in the phytoplankton of Lake Baikal, which have led to the disappearance of the main distinctive feature of the Baikalian phytoplankton – the alternation of extremely high (with the algal biomass over 1000 mg/m3) and extremely low (less than 100 mg/m3) productivity years. The ecological equilibrium appears to have shifted towards a new steady state.

The aim of the study was to test whether P-αB can be positioned as a preventing and treating agent for cardiovascular diseases.Materials and methods. The study was performed on sexually mature male Wistar rats. Endothelial dysfunction was modulated by a 7-days intraperitoneal administration of L-NAME at the dose of 2.5 mg/100 g. P-αB, or erythropoietin (EPO), was used for therapy at the dose of 2.5 µg/100 g × 3 times for 7 days, the total dose was 7.5 µg/100 g. The function of endothelium was estimated by an endothelium-dependent and endothelium-independent vasodilation. In addition, a histological assessment of the abdominal aortic wall state and the analysis of eNos, Tnf and Il-1β genes expression were performed. To estimate prothrombotic properties, P-αB and EPO were administered, at the doses of 2.5 and 5 µg/100 g (3 times a day for 7 days, the total doses were 7.5 µg/100 g and 15 µg/100 g, respectively) and on the 8th day, the time of ferric (III) chloride-induced carotid artery thrombosis was estimated.Results. Theresults of the functional tests for endothelium-dependent and endothelium-independent vasodilatation, as well as the histological picture of the aorta have evidenced that P-αB and EPO do not affect L-NAME-induced hypertension but improve the endothelium function. At the same time, P-αB shows a significantly higher endothelial-protective activity, reducing the coefficient of endothelial dysfunction from 5.1±0.15 to 2.72±0.12. In addition, P-αB has significantly increased the expression of eNos and reduced the expression level of Tnf and Il-1β mRNA genes. Carrying out Ferric (III) chloride-induced carotid artery thrombosis has revealed that P-αB (5 µg/100 g × 3 times a day for 7 days, total dose was 15 µg/100 g) has a lower but statistically significant prothrombotic activity than EPO.Conclusion. P-αB can be positioned as an atheroprotector because of its ability to prevent the death of endothelial cells, as well as to reduce remodeling and proinflammatory activation of the vascular wall. However, the prothrombotic properties of P-αB limit its use as a preventing and treating agent for atherosclerosis-associated diseases.

As a result of the breeding process, there are two main types of flax (Linum usitatissimum L.) plants. Linseed is used for obtaining seeds, while fiber flax is used for fiber production. We aimed to identify the genes associated with the flax plant type, which could be important for the formation of agronomically valuable traits. A search for polymorphisms was performed in genes involved in the biosynthesis of cell wall components, lignans, fatty acids, and ion transport based on genome sequencing data for 191 flax varieties. For 143 of the 424 studied genes (4CL, C3′H, C4H, CAD, CCR, CCoAOMT, COMT, F5H, HCT, PAL, CTL, BGAL, ABC, HMA, DIR, PLR, UGT, TUB, CESA, RGL, FAD, SAD, and ACT families), one or more polymorphisms had a strong correlation with the flax type. Based on the transcriptome sequencing data, we evaluated the expression levels for each flax type-associated gene in a wide range of tissues and suggested genes that are important for the formation of linseed or fiber flax traits. Such genes were probably subjected to the selection press and can determine not only the traits of seeds and stems but also the characteristics of the root system or resistance to stresses at a particular stage of development, which indirectly affects the ability of flax plants to produce seeds or fiber.

Flax (Linum usitatissimum L.) is used for the production of textile, oils, pharmaceuticals, and composite materials. Fusarium wilt, caused by the fungus Fusarium oxysporum f. sp. lini, is a very harmful disease that reduces flax production. Flax cultivars that are resistant to Fusarium wilt have been developed, and the genes that are involved in the host response to F. oxysporum have been identified. However, the mechanisms underlying resistance to this pathogen remain unclear. In the present study, we used transcriptome sequencing data obtained from susceptible and resistant flax genotypes grown under control conditions or F. oxysporum infection. Approximately 250 million reads, generated with an Illumina NextSeq instrument, were analyzed. After filtering to exclude the F. oxysporum transcriptome, the remaining reads were mapped to the L. usitatissimum genome and quantified. Then, the expression levels of cinnamyl alcohol dehydrogenase (CAD) family genes, which are known to be involved in the response to F. oxysporum, were evaluated in resistant and susceptible flax genotypes. Expression alterations in response to the pathogen were detected for all 13 examined CAD genes. The most significant differences in expression between control and infected plants were observed for CAD1B, CAD4A, CAD5A, and CAD5B, with strong upregulation of CAD1B, CAD5A, and CAD5B and strong downregulation of CAD4A. When plants were grown under the same conditions, the expression levels were similar in all studied flax genotypes for most CAD genes, and statistically significant differences in expression between resistant and susceptible genotypes were only observed for CAD1A. Our study indicates the strong involvement of CAD genes in flax response to F. oxysporum but brings no evidence of their role as resistance gene candidates. These findings contribute to the understanding of the mechanisms underlying the response of flax to F. oxysporum infection and the role of CAD genes in stress resistance.

This article presents the results of comparative studies of the frequency and distribution of chiasmata in pollen mother cells (PMCs) in five diploid tomato species, Solanum lycopersicum, S. pimpinellifolium, S. peruvianum, S. habrochaites, and S. neorickii, and one autotetraploid species, S. pimpinellifolium. It was established that under the same growing conditions, the total chiasma frequency in the cell depended on the species. At the same time, the green-fruited species S. peruvianum, S. neorickii, and S. habrochaites differed in distal chiasma frequency, while the red-fruited species S. lycopersicum and S. pimpinellifolium differed in interstitial chiasma frequency. It was shown that the total chiasma frequency in PMCs of plants of one species is a stable index of recombination potential that does not depend on the growing conditions. The redistribution between distal and interstitial chiasmata was found to be more variable, depending on the species, year, geographic growth conditions. In autotetraploid, the chiasma frequency per bivalent was lower than that in diploid S. pimpinellifolium plants, primarily due to interstitial chiasmata, the frequency of which remained at the level characteristic for diploid plants. It was concluded that the recombination plasticity of the tomato genomes was due to the redistribution of chiasmata along bivalents, and not to the change in their number in the cell.

In interspecific hybrids a decrease in genetic exchanges between chromosomes from different species and negative interactions between functionally incompatible loci limit genetic variation among the progeny. Earlier the fraction of crossover genotypes was increased in intraspecific hybrids of the cultivated tomato Solanum lycopersicum with the expression of the recA Escherichia coli gene. In this research transgenic hybrids between S. lycopersicum and some wild tomato species were obtained in order to study the effect of recA gene expression on the frequency of crossovers in the progeny of interspecific hybrids. Interspecific hybrids showed negative interactions between the loci of the cultivated tomato and the S. cheesmaniae, S. pimpinellifolium, and S. habrochaites species. In the latter case it resulted in semilethal necrosis. The recA gene expression in interspecific hybrids with S. cheesmaniae partially compensates among the F2 progeny the deficiency of recessive genotypes at the Wv:wv locus of chromosome 2. In general, the fractions of crossover genotypes in the F2 progeny were higher in transgenic interspecific hybrids than in control non-transgenic hybrids of the same combination of crossing, but lower than in intraspecific S. lycopersicum hybrids.

In cultivated tomato hybrids (Marglobe × Mo938), the anthocyanin-free gene shows linked inheritance with the d (dwarf) gene on chromosome 2, but with a recombination frequency approximately three times higher than that according to the genetic map and in other hybrids with the Marglobe line. Cytological analysis of the mother pollen cells of the hybrids (Marglobe × Mo938) revealed no abnormalities of meiotic division and segregation of chromosomes, as well as no decrease in fertility. By means of the functional allelism test, it was established that, unlike Mo500, Mo504, and Mo755 marker tomato lines, in Mo938 the anthocyanin-free trait is not determined by the aw (anthocyanin without) or aa (anthocyanin absent) genes of chromosome 2. Using the F2 progeny of interspecies hybrids (Mo938 × Solanum pimpinellifolium), independent inheritance of the anthocyanin-free gene relative to the wv (white virescent) and d marker genes, as well as to six SSR anchor markers distributed at different sites of chromosome 2, was established. Thus, the Mo938 tomato line carries the d and wv markers on chromosome 2, as well as the anthocyanin-free gene not belonging to chromosome 2.

Background Flax (Linum usitatissimum L.) is grown for fiber and seed in many countries. Flax cultivars differ in the oil composition and, depending on the ratio of fatty acids, are used in pharmaceutical, food, or paint industries. It is known that genes of SAD (stearoyl-ACP desaturase) and FAD (fatty acid desaturase) families play a key role in the synthesis of fatty acids, and some alleles of these genes are associated with a certain composition of flax oil. However, data on genetic polymorphism of these genes are still insufficient. Results On the basis of the collection of the Institute for Flax (Torzhok, Russia), we formed a representative set of 84 cultivars and lines reflecting the diversity of fatty acid composition of flax oil. An approach for the determination of full-length sequences of SAD1, SAD2, FAD2A, FAD2B, FAD3A, and FAD3B genes using the Illumina platform was developed and deep sequencing of the 6 genes in 84 flax samples was performed on MiSeq. The obtained high coverage (about 400x on average) enabled accurate assessment of polymorphisms in SAD1, SAD2, FAD2A, FAD2B, FAD3A, and FAD3B genes and evaluation of cultivar/line heterogeneity. The highest level of genetic diversity was observed for FAD3A and FAD3B genes – 91 and 62 polymorphisms respectively. Correlation analysis revealed associations between particular variants in SAD and FAD genes and predominantly those fatty acids whose conversion they catalyze: SAD – stearic and oleic acids, FAD2 – oleic and linoleic acids, FAD3 – linoleic and linolenic acids. All except one low-linolenic flax cultivars/lines contained both the substitution of tryptophan to stop codon in the FAD3A gene and histidine to tyrosine substitution in the FAD3B gene, while samples with only one of these polymorphisms had medium content of linolenic acid and cultivars/lines without them were high-linolenic. Conclusions Genetic polymorphism of SAD and FAD genes was evaluated in the collection of flax cultivars and lines with diverse oil composition, and associations between particular polymorphisms and the ratio of fatty acids were revealed. The achieved results are the basis for the development of marker-assisted selection and DNA-based certification of flax cultivars.

MIC and minimum biofilm bactericidal concentration (MBBC) values of eravacycline against 185 staphylococci from periprosthetic joint infections were determined. Staphylococcus aureus had MICs of ≤0.25 μg/ml. MICs for methicillin-susceptible and -resistant Staphylococcus epidermidis were ≤1 and ≤2 μg/ml, respectively. S. aureus and S. epidermidis MBBC 50 and MBBC 90 values were 8 and 16 μg/ml for each, showing poor anti-staphylococcal biofilm activity using the method studied.

This study describes two viral communities from the world&rsquo, s oldest lake, Lake Baikal. For the analysis, we chose under-ice and late spring periods of the year as the most productive for Lake Baikal. These periods show the maximum seasonal biomass of phytoplankton and bacterioplankton, which are targets for viruses, including bacteriophages. At that time, the main group of viruses were tailed bacteriophages of the order Caudovirales that belong to the families Myoviridae, Siphoviridae and Podoviridae. Annotation of functional genes revealed that during the under-ice period, the &ldquo, Phages, Prophages, Transposable Elements and Plasmids&rdquo, (27.4%) category represented the bulk of the virome. In the late spring period, it comprised 9.6% of the virome. We assembled contigs by two methods: Separately assembled in each virome or cross-assembled. A comparative analysis of the Baikal viromes with other aquatic environments indicated a distribution pattern by soil, marine and freshwater groups. Viromes of lakes Baikal, Michigan, Erie and Ontario form the joint World&rsquo, s Largest Lakes clade.

Background. Wilson’s disease (WD) is a rare inherited disorder caused by mutations in the ATP7B gene resulting in copper accumulation in different organs. However, data on ATP7B mutation spectrum in Russia and worldwide are insufficient and contradictory. The objective of the present study was estimation of the frequency of ATP7B gene mutations in the Russian population of WD patients. Materials and methods. 75 WDpatients were examined by next-generation sequencing (NGS). A targeted panel NimbleGen SeqCap EZ Choice: 151012_HG38_CysFib_EZ_HX3 (ROCHE)was designed for analysis of ATP7B gene and possible modifier genes. Retrospective assessment of a diagnostic WD score (Leipzig, 2001) was also performed. Results. 31 mutations in ATP7B gene were detected. Two most frequent mutations were c.3207C > A (51,85% of alleles) and c.3190 G > A (8,64% of alleles). Single rare mutations were detected in 29% of cases. In 96% cases mutations of both copies of the ATP7B were revealed. We also observed 3 novel potentially pathogenic variants which were not previously described (c.1870-8A > G, c.3655A > T (p.Ile1219Phe), c.3036dupC (p.Lys1013fs). For 25% of patients at the time of the manifestation the diagnosis WD could not be established using the earlier proposed diagnostic score. There was a remarkable delay in diagnosis for the majority of patients. Only 33% of patients WD was diagnosed in three months after the first symptoms, 29%patients - in 3–12 months, 30% – in 1–10 years, in 8% – more than 10 years. Generally, clinical appearance of WD may be rather variable at manifestation and genetic profiling at this step is the only way to confirm the presence of WD.

The objective of the present study was to assess the levels of Se, as well as other essential and toxic trace elements in wheat grains and traditional Roti-bread from whole-grain flour in a seleniferous area of Punjab (India) using inductively-coupled plasma mass-spectrometry. Wheat grain and bread selenium levels originating from seleniferous areas exceeded the control values by a factor of more than 488 and 179, respectively. Se-rich wheat was also characterized by significantly increased Cu and Mn levels. Se-rich bread also contained significantly higher levels of Cr, Cu, I, Mn, and V. The level of Li and Sr was reduced in both Se-enriched wheat and bread samples. Roti bread from Se-enriched wheat was also characterized by elevated Al, Cd, and Ni, as well as reduced As and Hg content as compared to the respective control values. Se intake with Se-rich bread was estimated as more than 13,600% of RDA. Daily intake of Mn with both Se-unfortified and Se-fortified bread was 133% and 190% of RDA. Therefore, Se-rich bread from wheat cultivated on a seleniferous area of Punjab (India) may be considered as a potent source of selenium, although Se status should be monitored throughout dietary intervention.

Flax (Linum usitatissimum L.) is a multipurpose crop which is used for the production of textile, oils, composite materials, pharmaceuticals, etc. Soil acidity results in a loss of seed and fiber production of flax, and aluminum toxicity is a major factor that depresses plant growth and development in acid conditions. In the present work, we evaluated gene expression alterations in four flax genotypes with diverse tolerance to aluminum exposure. Using RNA-Seq approach, we revealed genes that are differentially expressed under aluminum stress in resistant (Hermes, TMP1919) and sensitive (Lira, Orshanskiy) cultivars and selectively confirmed the identified alterations using qPCR. To search for differences in response to aluminum between resistant and sensitive genotypes, we developed the scoring that allowed us to suggest the involvement of MADS-box and NAC transcription factors regulating plant growth and development and enzymes participating in cell wall modifications in aluminum tolerance in flax. Using Gene Ontology (GO) enrichment analysis, we revealed that glutathione metabolism, oxidoreductase, and transmembrane transporter activities are the most affected by the studied stress in flax. Thus, we identified genes that are involved in aluminum response in resistant and sensitive genotypes and suggested genes that contribute to flax tolerance to the aluminum stress.

Field observations showed that the characteristics of chemical composition of waters and the development of plankton algae in the lakes within the delta of the Selenga river are determined by their flowage. The most open Lake Nekipelovskoe communicates with the Selenga outlets throughout a year, and Lake Zavernyaikha only at the period of an open channel. Lake Semenovskoe and Lake Khlystov Zaton are located in the islands and are isolated from the outlets. According to composition of main ions, the lakes under investigation refer to the hydrocarbonate class, the calcium group. The sum of ions in the water of Lake Nekipelovskoe approaches the one in the Selenga (86−221 mg/dm3), and the highest sums of ions were recorded in the wintertime in the lakes isolated from the outlets (446−743 mg/dm3). The lakes of the delta are characterized by a high trophicity. The maximum concentrations of total phosphorus in Lake Nekipelovskoe and Lake Zavernyaikha were 68 and 122 μg mg/dm3, and in Lake Semenovskoe and Lake Khlystov Zaton −0.8 and −0.63 μg mg/dm3, respectively. The most intense development of algae is observed in Lake Zavernyaikha, which is due to the high population of Baikal endemics. Lake Zavernyaikha showed a close negative correlation between the concentration of NO3−, mineral phosphorus and phytoplankton biomass; the correlation coefficient was −0.8 and −0.63, respectively. The lakes exhibited increased contents readily hydrolysable organic matter, and a decrease in dissolved oxygen concentration in winter; hydrogen sulfide was repeatedly recorded in Lake Khlystov Zaton. The water quality in the lakes during the springtime varies from “quite clean” to “weakly polluted”; at low-water periods, especially in winters, it can drop to the category of “exceedingly dirty”. The water quality of the Selenga can be influenced by the lakes during spring floods when material accumulated during the wintertime is transported to the river outlets and further to Lake Baikal.

We performed a regional analysis of the effect of anthropogenic (acid precipitation) and natural (climatic changes, endogenous methane) factors on the hydrochemical composition and phytoplankton of mountain lakes in East Siberia for the last 210 years. The lacustrine diatom community responded to the intense acid precipitation that led to the acidification of lakes in Europe and North America in 1950–1985: Cyclotella-complex was partly replaced by more pH-tolerant species of diatoms, such as Aulacoseira lirata, A. italica, and Tabellaria flocculosa. This anthropogenic impact, however, was not dramatic for the ecosystem of mountain Lake Oron. The diatom records distinctly show a tendency for the reduction of lacustrine-alga population since the end of the Little Ice Age. We assume that the decrease in the Oron bioproductivity was mainly due to a deficit of nutrients caused by the inflow of ultrafresh waters from the thawing glaciers, snow patches, and seasonal snow cover of the Kodar Ridge during the Recent global warming in the Northern Hemisphere. In addition, the changes in the lake ecosystem might have been accelerated by emissions of endogenous methane.

The world is dedicated to studies recombinogenesis in evolution and selection, on the variability causes of recombination and segregation parameters in hybridological analysis. The necessity of a careful choice in control unit for recombination experiment dependent on the architecture of a species reproductive system.

Sticky bacteria tolerated as future food Dictyostelium discoideum amoebae consume bacteria until the supply is exhausted. Then the amoeba cells clump together into a “slug” and initiate a complex multicellular reproductive phase. Specialized cells within aggregates rid the slug of any extracellular bacteria. However, some strains of amoeba tolerate live, intracellular bacteria. Dinh et al. discovered that these carrier strains bear surface lectins that bind Klebsiella bacteria, promote cell entry, and prevent the bacteria from being immediately digested. These bacteria then provide a future food source. Moreover, the internalized bacteria transfer DNA into the amoeba nucleus, resulting in transient genetic transformation. Science , this issue p. 402

The recombinant E7 oncoprotein gene of type 16 human papilloma virus (conjugated with the heat shock protein 70 (E7(16)-HSP70)) was expressed in Saccharomyces cerevisiae yeast cells. A number of chromatographic isolations were conducted to obtain the target protein and its primary identification and to establish its originality. The use of metal chelate chromatography was based on selective binding of sorbent active groups with a poly-histidine fragment at C-terminus of the target protein polypeptide sequence, while the use of affine chromatography was based on the association with ATP-binding regions of E7 and HSP70. The degree of purity of the target protein after both procedures did not exceed 70%, indicating the presence of many low-molecular admixtures and products of the target molecule oligomerization. The use of chromatographic purification under denaturing conditions using strong reducing agents allowed isolation of the target protein, the monomer content in which exceeded 97%. The target protein originality was established by immunoblotting and electrophoresis; the correspondence of its primary structure to the declared sequence was demonstrated by mass-spectrophotometry.

A gene for a recombinant E7 oncoprotein of human papillomavirus type 16 conjugated with a heat shock protein 70 (E7(16)-HSP70) has been expressed in Saccharomyces cerevisiae. A number of chromatographic separations was performed in order to primarily identify the protein and establish its authenticity. Metal-chelate and affinity chromatography were aimed at selective binding of the active groups of sorbents with polyhistidine fragment at the C-terminus of the polypeptide sequence of the target protein and ATP-binding regions of E7 and HSP70, respectively. The purity of the target protein after two purification steps did not exceed 70% showing the presence of a number of low-molecular impurities and oligomerization products of the target molecule. Chromatographic purification under denaturing conditions using strong reducing agents made it possible to isolate the target protein with the content of the monomer exceeding 97%. Electrophoresis and immunoblotting methods permitted to establish the authenticity of the target protein, and mass spectrometry showed its set primary structure.

Alexi M. Gracheva*, Eugene A. Vaganova, Steven W. Leavittb, Irina P. Panyushkinab, Eugene P. Chebykinc, Vladimir V. Shishova, Natalia A. Zhuchenkoc, Anastasia A. Knorred, Malcolm K. Hughesb and Mukhtar M. Naurzbaevd a Siberian Federal University, 79 Svobodny, Krasnoyarsk, 660041 Russia b Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ 85721, USA c Limnological Institute SB RAS, 3 Ulan-Batorskaya, Irkutsk 664033 Russia d V. N. Sukachev Institute of Forest SB RAS, 50/28 Akademgorodok, Krasnoyarsk, 660036 Russia

The problems of study and utilization of plant germplasm collections and arrangement of genetic resources based on botanical, functional, morphological, biochemical, and genetical principles are underlined in the article. The types of identified and systemized germplasm collections and genetic resources of flowering plants are described. The search path and methods of identification, differentiation, arrangement, and selection of genetic donors and germplasm collections of traits of ontogenetic and phylogenetic adaptation are shown in the article.

This work addresses the isotopic heterogeneity of the Archean lithospheric mantle by the example of high-Mg, moderate-alkali, LILE and LREE-enriched Panozero sanukitoid massif, which is located in the Central Karelia, southeastern Baltic Shield. Initial Nd and Sr isotope characteristics were determined for mantle source of the massif. ɛNd(T) in the source are plotted below DM line, varying from + 0.7 to + 1.4 (+1.1, on average). The 87Sr/86Sr(T) ∼ 0.7017 significantly exceeds that of depleted mantle and reflects change of Rb/Sr ratio in the source due to metasomatic reworking of mantle. Data on Pb isotope composition of potassium feldspars indicate that source of monzonites of the Panozero Massif had lower μ (238U/204Pb) = 8 and higher (238Th/232U) = 4.05 relative to primitive mantle.

The high-K and high-Mg Panozero central-type intrusion is located on the shore of Lake Segozero, Central Karelia, and has an age of 2737 ± 10 Ma. Detailed mapping and petrological study showed that it was formed in three magmatic cycles that were separated by lamprophyre dikes. The first cycle is composed mainly of mafic rocks (layered complex: pyroxenites-honblendites-monzogabbro) and monzonites 1; the second cycle includes monzonites 2, and the third cycle comprises monzonites 3 and quartz monzonites. The massif is cut by numerous lamprophyre dikes and breccia zones. As compared to calc-alkaline series, the studied rocks are enriched in K, Ba, Sr, P, LREE, have high mg# (mg# = 0.5–0.65), and elevated contents of Cr and Ni. The parent composition of the layered complex was determined to be monzogabbro. Model calculations showed that the compositional variations of the Panozero Complex are consistent with the fractional crystallization of monzogabbro. The melts were fractionated in an intermediate chamber and during the flowing and crystallization of the magma. The parent melt of the intrusion was formed by the partial melting of mantle enriched in some LILE, LREE, and volatiles (CO2 and H2O). The volatile enrichment of the melt manifests itself in the mineral composition of the rocks, the presence of primary gas inclusions in apatite, and diverse structural features. The comparison of the rocks of the Panozero Massif with metasomatized mantle xenoliths in the variation diagrams for incompatible elements showed that the mantle source of the Panozero Complex was metasomatized by fluid consisting of H2O and CO2 of different origin.

Social amoebae feed on bacteria in the soil, but they aggregate when starved and form a migrating slug that will undergo fruiting body morphogenesis to produce terminally differentiated spores and stalk cells. We describe a new cell type in the social amoeba which appears to provide detoxification and immune-like functions, which we term Sentinel (S) cells. S cells were observed to engulf bacteria and sequester toxins while circulating within the slug, eventually being sloughed off. A Toll/Interleukin-1 Receptor (TIR) domain protein, TirA, was also required for some S cell functions and for vegetative amoebae to feed on live bacteria. This apparent innate immune function in social amoebae, and the use of TirA for bacterial feeding, suggests an ancient cellular foraging mechanism that may have been adapted to defense functions well before the diversification of the animals.

Motivation: Coordinate regulation of gene expression can provide information on gene function. To begin a large-scale analysis of Dictyostelium gene function, we clustered genes based on their expression in wild-type and mutant strains and analyzed their functions. Results: We found 17 modes of wild-type gene expression and refined them into 57 submodes considering mutant data. Annotation analyses revealed correlations between co-expression and function and an unexpected correlation between expression and function of genes involved in various aspects of chemotaxis. Co-regulation of chemotaxis genes was also found in published data from neutrophils. To test the predictive power of the analysis, we examined the phenotypes of mutations in seven co-regulated genes that had no published role in chemotaxis. Six mutants exhibited chemotaxis defects, supporting the idea that function can be inferred from co-expression. The clustering and annotation analyses provide a public resource for Dictyostelium functional genomics. Supplementary information: http://dictygenome.org/supplement/gadi/okyay_2005/ Contact: gadi@bcm.tmc.edu

The molecular components of mammalian circadian clocks are elusive. We have isolated a human gene termed RIGUI that encodes a bHLH/PAS protein 44% homologous to Drosophila period. The highly conserved mouse homolog (m-rigui) is expressed in a circadian pattern in the suprachiasmatic nucleus (SCN), the master regulator of circadian clocks in mammals. Circadian expression in the SCN continues in constant darkness, and a shift in the light/dark cycle evokes a proportional shift of m-rigui expression in the SCN. m-rigui transcripts also appear in a periodic pattern in Purkinje neurons, pars tuberalis, and retina, but with a timing of oscillation different from that seen in the SCN. Sequence homology and circadian patterns of expression suggest that RIGUI is a mammalian ortholog of the Drosophila period gene, raising the possibility that a regulator of circadian clocks is conserved.

A polymorphic CAG repeat was identified in the human alpha 1A voltage-dependent calcium channel subunit. To test the hypothesis that expansion of this CAG repeat could be the cause of an inherited progressive ataxia, we genotyped a large number of unrelated controls and ataxia patients. Eight unrelated patients with late onset ataxia had alleles with larger repeat numbers (21-27) compared to the number of repeats (4-16) in 475 non-ataxia individuals. Analysis of the repeat length in families of the affected individuals revealed that the expansion segregated with the phenotype in every patient. We identified six isoforms of the human alpha 1A calcium channel subunit. The CAG repeat is within the open reading frame and is predicted to encode glutamine in three of the isoforms. We conclude that a small polyglutamine expansion in the human alpha 1A calcium channel is most likely the cause of a newly classified autosomal dominant spinocerebellar ataxia, SCA6.

The X-linked developmental mouse mutations bare patches (Bpa) and striated (Str) may be homologous to human X-linked dominant chondrodysplasia punctata (CDPX2) and incontinentia pigmenti (IP2), respectively, based on their genetic mapping and clinical phenotypes. Bpa and Str have been localized to an overlapping critical region of 600 kb that demonstrates conserved gene order with loci in human Xq28 between DXS1104 and DXS52. As part of efforts to isolate the genes involved in these disorders, we have begun to develop a comparative transcription map spanning this region in both species. Using techniques of cross-species conservation and hybridization, exon trapping, and cDNA selection we have identified four known genes or members of gene families--caltractin, a member of the gamma-aminobutyric acid (GABAA) receptor gene family, a member of the melanoma antigen gene (MAGE) family, and several members of the murine-specific, X-linked lymphocyte regulated gene (Xlr3) family. Trapped exons and, in some cases, longer cDNAs have been isolated for potentially 7-9 additional genes. One cDNA demonstrates highly significant homology with members of the Krüppel family of zinc finger transcription factors. A second novel cDNA demonstrates homology at the 3' end of the predicted amino acid sequence to a LIM domain consensus. Gene order appears conserved among those cDNAs determined to be present in both human and mouse. Three of the murine transcripts appear to be present in multiple copies within the Bpa/Str critical region and could be associated with a predisposition to genomic rearrangements. Reverse transcriptase PCR (RT-PCR) and Northern analysis demonstrate that several of the transcripts are expressed in mid-gestation murine embryos and neonatal skin, making them candidates for the Bpa and Str mutations and their respective homologous human disorders.

The results of detailed study of the Urosozero greenstone structure (northwestern part of the Vodlozero domain) of the Fennoscandian Shield are presented. The composition and the U-Pb zircon age of the volcanic rocks were studied. The Urosozero structure is composed mainly of mafic-felsic volcanic rocks rather than the sediments. Mafic and ultramafic volcanics were obtained under high degree source melting followed by crustal contamination. Intermediate and acid volcanics vary from andesites to rhyolites and are similar in composition to the volcanics of the Shiloss and Lake Kamennoe greenstone structures. The methamorphism of dacites occurred at T = 400–610 °С and P > 4 kbar. SIMS SHRIMP-II U-Pb dating of the dacite specimen was carried out on separate zircon grains at the Centre of Isotopic Research (VSEGEI, St. Petersburg). The ages received include 2875 ± 9 Ma as the time of volcanism and 2709 ± 8 Ma as the time of metamorphism. So, the volcanism of the Uros greenstone structure is synchronous with the volcanism of the northern Vodlozero domain.

The expansion of polyglutamine tracts encoded by CAG trinucleotide repeats is a common mutational mechanism in inherited neurodegenerative diseases. Spinocerebellar ataxia type 6 (SCA6), an autosomal dominant, progressive disease, arises from trinucleotide repeat expansions present in the coding region of CACNA1A (chromosome 19p13). This gene encodes alpha(1A), the principal subunit of P/Q-type Ca(2+) channels, which are abundant in the CNS, particularly in cerebellar Purkinje and granule neurons. We assayed ion channel function by introduction of human alpha(1A) cDNAs in human embryonic kidney 293 cells that stably coexpressed beta(1) and alpha(2)delta subunits. Immunocytochemical analysis showed a rise in intracellular and surface expression of alpha(1A) protein when CAG repeat lengths reached or exceeded the pathogenic range for SCA6. This gain at the protein level was not a consequence of changes in RNA stability, as indicated by Northern blot analysis. The electrophysiological behavior of alpha(1A) subunits containing expanded (EXP) numbers of CAG repeats (23, 27, and 72) was compared against that of wild-type subunits (WT) (4 and 11 repeats) using standard whole-cell patch-clamp recording conditions. The EXP alpha(1A) subunits yielded functional ion channels that supported inward Ca(2+) channel currents, with a sharp increase in P/Q Ca(2+) channel current density relative to WT. Our results showed that Ca(2+) channels from SCA6 patients display near-normal biophysical properties but increased current density attributable to elevated protein expression at the cell surface.

One of the largest environmental polluters in Chapaevsk (Samara Region, Russia) is the Middle Volga chemical plant. From 1967 to 1987, it produced hexachlorocyclohexane (lindane) and its derivatives. Currently, it produces crop protection chemicals (liquid chlorine acids, methyl chloroform, vinyl chloride, and some other chemicals). Dioxins were detected in air (0.116 pg/m3), in soil (8.9-298 ng/kg), in the town's drinking water (28.4-74.1 pg/liter), and in the cow's milk (the content of 2,3,7,8-TCDD was 17.32 pg TEQ/g fat). The mean content of dioxins in seven pooled samples of human milk (40 individual trials) was 42.26 pg TEQ/g fat, in four female workers' blood samples -412.4 pg TEQ/g fat, in six residents blood samples (those who lived 1-3 km from the chemical plant) -75.2 pg TEQ/g fat, in four residents' blood samples (5-8 km from the plant) -24.5 pg TEQ/g fat. To assess cancer risk and reproductive health status, official medical statistical information was used. In general, the male cancer mortality observed rate in Chapaevsk is higher than expected. The SMR is higher for lung cancer 3.1(C.I. 2.6-3.8), urinary organs 2.6(C.I. 1.7-3.6). Chapaevsk women have a higher risk overall due to breast cancer 2.1(C.I. 1.6-2.7) and cervix cancer 1.8(C.I. 1.0-3.1). The incidence rates were higher for lung cancer in males and for female breast cancer in all age groups compared to Russia and Samara Region in 1998. Significant disruptions in reproductive function were detected. The mean frequency of spontaneous abortions in the last seven years was statistically higher 24.4% in Chapaevsk (compared to other of the towns region). The average rate of premature labor was 45.7 per 1000 women in Chapaevsk that is significantly higher than in most Samara Region towns. The frequency of newborns with low birth weight was 7.4%. In Russia and in most of the Samara Region towns, this rate is lower (6.2-5.1%) but not statistically different. For the determination of congenital morphogenetic conditions (CMGC), 369 children born between 1990 and 1995 were examined. The average number of CMGC per child was significantly higher, 4.5 for boys and 4.4 for girls. The first results indicated serious disruptions associated with high dioxin levels in human milk and blood in Chapaevsk. We suggest that Chapaevsk is an incredibly interesting site for further environmental-epidemiological research to assess the impact of dioxins on human health.

Reciprocal probing has been used to identify a cDNA clone (xh8H11) representing a gene preferentially expressed in striated muscle. The gene maps close to DXS7101 31.9 cM from the short arm telomere of the X-chromosome at Xp22.1. On searching expressed and genomic databases, 21 expressed sequence tags were found that allowed the assignment of a human extended consensus sequence of 887 bp, suggesting a completely expressed gene symbolized as SMPX. By using the human consensus sequence, the orthologous mouse Smpx and rat SMPX genes could be aligned and confirmed by complete sequencing of additional SMPX-related clones obtained by library screening. An open reading frame was identified encoding a peptide of 88-86 and 85 amino acids in human and rodents, respectively. The predicted peptide had no significant homologies to known structural elements. The human consensus cDNA sequence was used to define the genomic structure of the human SMPX that had been missed by a previous large scale sequencing approach. The gene consists of five exons (or =172, 57, 84, 148,or =422 bp) and four introns (3639, 10410, 6052, 31134 bp) comprising together 52.1 kb and is preferentially and abundantly expressed in heart and skeletal muscle. Thus, a novel human gene encoding a small muscular protein that maps to Xp22.1 (SMPX) has been identified and structurally characterized as a basis for further functional analysis.

The recombination frequency (rf) is known to be dependent not only on genetic background, but on the environment as well. In our numerical experiments we examine the role of the dependence of recombination on environment in the evolution of the genetic system. Variable rf-strategies, ensuring mean fitnesses greater than the optimum constant rf(*)-level, exist in both cyclical and stochastic environments. The conclusion that environment dependent recombination is evolutionary advantageous can be shown to be valid when variation in the frequency of recombination modifiers rather than mean fitness (which implies the concept of group selection) is used as a criterion for strategy comparisons. In this case, an evolutionary advantageous type of variable rf-strategies is the one ensuring restricted genetic variability dispersion in an optimal environment and an increase in released variation with the deterioration of environmental conditions. Another important result is that, taking into account the dependence of recombination on environment, it is possible to account for the maintenance of a higher level of population recombination than that predicted by models with the constant rf-level. On the whole, the data obtained indicate that the direct influence of external factors upon the rf-value could have been a significant factor in the evolution of the genetic system.

Significant differences among cage populations ofDrosophila in the dynamics of linkage disequilibrium for marker locib, cn andvg of chromosome 2 have been found at optimum and extreme temperatures. Fifteen generations of selection under extreme conditions considerably increased recombination frequency in thecn-vg region and over the whole of theb-vg interval. From the data obtained it is inferred that recombination-promoting alleles with intermediate expression in the heterozygous state are responsible for these changes.

Some consequences of the effect of environmental factors on the recombination system are dealt with in this paper. There are two components involved - the system of individual adaptation (F-system) and the genetic system of population adaptation (R-system). Their interaction offers an optimum interrelation of immediate adaptivity and genetic flexibility within the population. Familiar data on the evolution of recombination control systems are considered in connection with the problems of induced broadening of genotypic variation spectrum with a view to selection.A notion of combined recombination rate and spectrum control is introduced here: disturbance control-due to direct influence of environmental factors on R-system (including meiotic processes), negative feedback control - due to dominance-recessiveness relationship between rec-loci alleles of the "fine" control system, and to the dependence of the R-system on the F-system norms of reaction to environment variation. The problem of dependence of the recombination spectrum on environmental factors has been considered and the hypothesis of a possible mechanism of such a dependence suggested.

Aim: To study and compare the expression patterns of mucins in the fetal gastroesophageal junction (GEJ) region and adenocarcinomas of the GEJ in adults using histochemical method. Material and Methods: To reveal the expression of different mucins, tissue sections from formalin-fixed paraffin-embedded tissue blocks of fetal GEJ and carcinomas of GEJ were stained by the following histological stains: hematoxylin and eosin, periodic acid-Schiff (PAS), alcian blue (AB), pH 2.5, combined AB-PAS, and combined AB-Aldehyde Fuchsin (AB/AF). Results: Expression of mucins within the developing fetal GEJ has been demonstrated (gestational age 5–38 weeks). We studied histochemical features of neoplastic cells in carcinomas of GEJ from 90 adult patients. The results showed that in gastric type expression of neutral mucins dominated especially in well differentiated (G1) adenocarcinomas and corresponded to the last three months of GEJ development, while in the intestinal and mixed type significant acid mucins expression was detected in moderate (G2) and poorly (G3) differentiated adenocarcinomas and corresponded to 17–25 weeks of GA. No significant coincidence in mucins expression was observed in signet ring cell carcinomas in relation to GA. Conclusion: Our data suggest that decrease of neutral mucins level can be considered reliable phenotypic marker of poor prognosis of GEJ adenocarcinomas. Study of the developmental expression of mucin genes may improve understanding of the malignant transformation of esophageal tissue. Key Words: mucin expression, gastroesophageal junction, adenocarcinoma.

Hybrid genes containing the reporter gene for thermostable lichenase and model genes rec A, rec A1, cry3a, cry3aM, and ssp1 were constructed. The expression of these genes was studied in prokaryotic and eukaryotic cells. The presence of lichenase in the hybrid proteins was shown to facilitate analysis of the hybrid protein expression in transgenic organisms. Owing to high relative activity and thermostability of lichenase, the activity of this enzyme can be measured by simple, rapid and sensitive qualitative and quantitative methods that do not require costly equipment and reagents. Using the zymograms method, molecular masses of the lichenase-containing hybrid proteins can be precisely estimated. This method is proposed instead of Western blotting using lichenase as a translational reporter. Our results showed that the use of thermostable lichenase as a translational reporter yields the data that are problematic to obtain using traditional methods of gene expression analysis, which is of importance for fundamental and applied research.

To study and induce meiotic recombination in plants, we generated and analyzed transgenic tomato hybrids F1-RecA and F1-NLS-recA-LicBM3 expressing, respectively, the recA gene of Escherichia coli and the NLS-recA-licBM3 gene. It was found that the recA and NLS-recA-licBM3 genes are inherited through the maternal and paternal lineages, they have no selective influence on the pollen and are contained in tomato F1-RecA and F1-NLS-RecA-LicBM3 hybrids outside the second chromosome in the hemizygous state. The comparative analysis of the meiotic recombination frequency (rf) in the progenies of the transgenic and nontransgenic hybrids showed that only the expression of the recA gene of E. coli in cells of the F1-RecA plants produced a 1.2–1.5-fold increase in the frequency of recombination between some linked marker genes of the second chromosome of tomato.