A high coverage reference transcriptome assembly of pea (Pisum sativum L.) mycorrhizal roots.

Arbuscular mycorrhiza (AM) is an ancient mutualistic symbiosis formed by 80-90 % of land plant species with the obligatorily biotrophic fungi that belong to the phylum Glomeromycota. This symbiosis is mutually beneficial, as AM fungi feed on plant photosynthesis products, in turn improving the efficiency of nutrient uptake from the environment. The garden pea (Pisum sativum L.), a widely cultivated crop and an important model for genetics, is capable of forming triple symbiotic systems consisting of the plant, AM fungi and nodule bacteria. As transcriptomic and proteomic approaches are being implemented for studying the mutualistic symbioses of pea, a need for a reference transcriptome of genes expressed under these specific conditions for increasing the resolution and the accuracy of other methods arose. Numerous transcriptome assemblies constructed for pea did not include mycorrhizal roots, hence the aim of the study to construct a reference transcriptome assembly of pea mycorrhizal roots. The combined transcriptome of mycorrhizal roots of Pisum sativum cv. Frisson inoculated with Rhizophagus irregularis BEG144 was investigated, and for both the organisms independent transcriptomes were assembled (coverage 177x for pea and 45x for fungus). Genes specific to mycorrhizal roots were found in the assembly, their expression patterns were examined with qPCR on two pea cultivars, Frisson and Finale. The gene expression depended on the inoculation stage and on the pea cultivar. The investigated genes may serve as markers for early stages of inoculation in genetically diverse pea cultivars.

[THERMAL STABILITY AS A PROGNOSTIC INDICATOR OF CONSERVATION OF LIVE EMBRYONIC SMALLPOX VACCINE (TEOVAC) DURING STORAGE].

AIM: Determination of values of coefficients of thermal stability of TEOVac for prognosis of conservation of the vaccine (specific biological activity) during the process of warranty period storage. MATERIALS AND METHOD: TEOVac (masticatory tablets) in primary packaging was kept at increased temperature (accelerated and stress-tests) and at the conditions established by PAP for the preparation (long-term tests). Biological activity of the vaccine was determined by titration on 12-day chicken embryos. RESULTS: A correlation between the value of coefficients of thermal stability and conservation of the prepared series of the condition preparation at the final date of storage was experimentally established. CONCLUSION: Coefficients of thermal stability could be used as a prognostic indicator of quality of the produced pelleted formulation of the preparation for evaluation of conservation of the vaccine during warranty period storage.

[The Principle of Genome Complementarity in the Enhancement of Plant Adaptive Capacities].

In the present work, the potential for the enhancement of the adaptive capacity of microbe-plant systems (MPSs) through the integration of the symbiosis partners' genomes is considered on the example of different types of symbiotic relationships. The accumulated data on the genetic control of interactions for both the plant and microbe, which are discussed in the paper with respect to signaling genes, suggest that it is the complementarity of genetic determinants that underlies the successful formation of MPSs. A eukaryotic genome with limited information content, which is stable throughout a generation, is complemented by a virtually unlimited prokaryotic metagenome. The microsymbiont's ability to adapt to different living conditions is based on the restructuring of the accessory genome by different mechanisms, which are likely to be activated under the influence of plants, although the details of such a regulation remain unknown. Features of the genetic control of the interaction, particularly its universal character for different symbionts, allow us to formulate a principle of genome-complementarity with respect to interacting organisms and consider it an important factor, an adaptation that enhances the abilities of M PSs for their sustainable development in natural ecosystems and for high plant productivity in agrocenoses.

KNOTTED1-LIKE HOMEOBOX 3: a new regulator of symbiotic nodule development.

KNOX transcription factors (TFs) regulate different aspects of plant development essentially through their effects on phytohormone metabolism. In particular, KNOX TF SHOOTMERISTEMLESS activates the cytokinin biosynthesis ISOPENTENYL TRANSFERASE (IPT) genes in the shoot apical meristem. However, the role of KNOX TFs in symbiotic nodule development and their possible effects on phytohormone metabolism during nodulation have not been studied to date. Cytokinin is a well-known regulator of nodule development, playing the key role in the regulation of cell division during nodule primordium formation. Recently, the activation of IPT genes was shown to take place during nodulation. Therefore, it was hypothesized that KNOX TFs may regulate nodule development and activate cytokinin biosynthesis upon nodulation. This study analysed the expression of different KNOX genes in Medicago truncatula Gaertn. and Pisum sativum L. Among them, the KNOX3 gene was upregulated in response to rhizobial inoculation in both species. pKNOX3::GUS activity was observed in developing nodule primordium. KNOX3 ectopic expression caused the formation of nodule-like structures on transgenic root without bacterial inoculation, a phenotype similar to one described previously for legumes with constitutive activation of the cytokinin receptor. Furthermore, in transgenic roots with MtKNOX3 knockdown, downregulation of A-type cytokinin response genes was found, as well as the MtIPT3 and LONELYGUY2 (MtLOG2) gene being involved in cytokinin activation. Taken together, these findings suggest that KNOX3 gene is involved in symbiotic nodule development and may regulate cytokinin biosynthesis/activation upon nodule development in legume plants.

[Comigration of root nodule bacteria and bean plants to new habitats: coevolution mechanisms and practical importance (review)].

The review summarizes the results of studies on the comigration of tubercular bacteria and bean plants to new habitats, which is often accompanied by a decrease in the symbiosis efficiency due to a loss of the diversity of genes responsible for the interaction. This migration may lead to a rise in new symbionts as a result of gene transfers from initial symbionts to local bacteria. It was demonstrated that typically new symbionts lack an ability for N2 fixation but are highly competitive, blocking the inoculation of bean cultures by industrial strains. The design of coadapted systems of recognition and signal interaction of partners is a perspective approach to ensure competitive advantages of efficient rhizobia strains introduced into agrocenoses, together with host plants, over inactive local strains.

[Validation of the modified algorithm for predicting host susceptibility to viruses taking into account susceptibility parameters of primary target cell cultures and natural immunity factors].

The paper presents results of testing a modified algorithm for predicting virus ID50 values in a host of interest by extrapolation from a model host taking into account immune neutralizing factors and thermal inactivation of the virus. The method was tested for A/Aichi/2/68 influenza virus in SPF Wistar rats, SPF CD-1 mice and conventional ICR mice. Each species was used as a host of interest while the other two served as model hosts. Primary lung and trachea cells and secretory factors of the rats' airway epithelium were used to measure parameters needed for the purpose of prediction. Predicted ID50 values were not significantly different (p = 0.05) from those experimentally measured in vivo. The study was supported by ISTC/DARPA Agreement 450p.

[Quantitative assessment of in vitro neutralizing activity of secretory factors from rat lungs against influenza virus].

Secretory factors were isolated by lung wash followed by centrifugation to remove cells, dialysis of supernatant to remove NaCl salt, lyophilization of the lavage fluid and resuspention of the lyophilization product in an isotonic NaCl solution. It was shown that biological activity of influenza virus /Aichi/2/68 (3N2) significantly decreased (p = 0,01) from 8,17 +/- 0,10 to 7,14 +/- 0,20 IgEID50/ml during its incubation with secretory factors at 37 degrees C for 1 hr and to 7,92 +/- 0,17 IgEID50/ml in isotonic NaCl solution in the absence of these factors. Their concentration in the incubation medium was estimated to be 9.1 +/- 0.7% of their level in the lungs.

[Molecular genetic mechanisms used by legumes to control early stages of mutually beneficial (mutualistic) symbiosis].

Recent data on the plant control of early stages of mutually beneficial (mutualistic) symbioses of legumes, the mechanisms of perception and transmission of the microsymbiont's molecular signals in the macrosymbiont's cells, and induction of the genetic programs of the development of symbiotic compartments and organs of the plant are summarized. It is demonstrated that the genetic system of the plant controlling the development of nitrogen-fixing symbiosis of legumes (symbiotic root nodules), which emerged 70-80 Ma ago, has undoubtedly evolved on the basis of the genetic system controlling the development of the symbiosis with arbuscular mycorrhizal fungi (which emerged 40-500 Ma ago. Interactions between genes and between gene products, as well as exchange of molecular signals, form the basis of mutually beneficial (mutualistic) plant-bacterium interactions. Even in the case of a highly specific nitrogen-fixing symbiosis of legumes (symbiotic nodules), the receptors perceiving the signal from root-nodule bacteria may function in different ways. The development of arbuscular mycorrhiza and nitrogen-fixing symbiosis in legumes is a multistep process involving hundreds of genes of both the macro- and microsymbionts. For the symbioses to develop successfully, these genes should act in a coordinated way in the newly formed superorganismal system. Further studies are necessary to shed light onto the complexity of the plant genetic control of the development of mutualistic symbioses in legumes and provide information required for improving their functions in adaptive plant-breeding systems.

[Effect of exogenous thyroxin on renal ion-regulating and acid-secreting functions in white rats].

Experimental hyperthyreosis was stimulated by intraventricular injections of sodium solithyroxin (T4) suspension on 1% starch gel during 10 days at a dose of 10 microg/100 g of body mass (n = 15) or 20 microg/100 g of body mass (n = 15). Renal function was tested by 5 % water loading after 24 hrs. since the last T4 injection. Urine and blood plasma samples were analyzed for creatinine; in addition, urine was analyzed for sodium and potassium ions of titrated acids, ammonium cations, and pH. Thyroxin was found to decrease creatinine clearance and expedite renal excretion of sodium and potassium ions irrespective of the amount of exogenous T4; at the same time, exaggerated excretion of titrated acids and ammonium cations correlated with T4 dose.

[Comparative analysis of the susceptibility and productivity of respiratory tract target cells of mice and rats exposed to inflienza virus in vitro].

The levels of susceptibility to influenza virus A/Aichi/2/68 H3N2 and the virus yield were determined using primary cells of the trachea and lungs of CD-1 mice and Wistar rats, and for 3 sets of cells obtained from primary lung cells of the both species by centrifugation in the gradient of density and by sedimentation on a surface. The values of ID50 virus dose for 10(6) cells and virus yield per 1 infected cell determined for primary mice cells were 4.0+/-0.47 and 3.2+/-0.27 IgEID50 (lung cells), 3.8+/-0.17 and 3.3+/-0.20 IgEID50 (tracheal cells), and those determined for primary rat cells were 4.0+/-0.35 and 2.1+/-0.24 IgEID50 (lung cells), 3.7+/-0.27 and 2.2+/-0.46 IgEID50 (tracheal cells). The values of ID50 and yield measured for mixtures of cells obtained from primary lung cells by centrifugation in gradient of density and by sedimentation on a surface differed insignificantly (p = 0.05) from the values of the corresponding parameters measured for lung and tracheal cells for both rats and mice. The analysis of data on the variation of the concentrations of different cell types in the experimental cell mixtures shows that type 1 and 2 alveolocytes possess significantly lower (p = 0.05) susceptibility and productivity vs. ciliated cells of the both species. The investigation was conducted within the frame of the ISTC/DARPA#450p project.

[Regulatory genes of garden pea (Pisum sativum L.) controlling the development of nitrogen-fixing nodules and arbuscular mycorrhiza: a review of basic and applied aspects].

The review sums up the long experience of the authors and other researchers in studying the genetic system of garden pea (Pisum sativum L.), which controls sthe development of nitrogen-fixing symbiosis and arbuscular mycorrhiza. A justified phenotypic classification of pea mutants is presented. Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza) is mobilized.

[A study of possibility to predict the sensitivity of different respiratory tract divisions to influenza].

To predict a potential value of a viral ID50 for a macro-organism of interest (e.g. humans), it is necessary to determine in vitro two parameters of the interaction of the virus with susceptible cells of the host, i.e. the probability of the virus' productive absorption on a susceptible cell and the average virus yield per cell. A different macroorganism (a model animal) and primary cells obtained from it can be used to determine the value of a scale factor, which accounts for the difference between the values of the probability of the virus' absorption measured in vivo and in vitro. An original mathematical model is used to convert the above-mentioned data to ID50 for the macroorganism of interest. It was shown that the method of cultivating influenza virus (A/ Aichi/2/68) in primary suspension culture of respiratory tract cells of rats and two breeds of mice may be used to estimate potential human susceptibility to novel influenza viruses. This work was sponsored by DAPRA, USA, and performed under the contract 450p to the International Science and Technology Center, Moscow.

[The avidicity index of specific IgG in the diagnosis of diseases caused by west Nile and tickborne encephalitis viruses].

The significant antigenic crossovers between West Nile virus (WNV) and tick-borne encephalitis virus (TBEV) make the immunological diagnosis of these diseases difficult. The avidicity index of virus-specific class G immunoglobulins (IgG) was used as a criterion for the differentiation of an immune response to WNV or TBEV in patients and convalescents. The panels of the sera sampled from patients with tick-borne encephalitis and convalescents in the Novosibirsk and Tomsk Regions and in the Primorye Territory and from those with West Nile fever and convalescents in the Volgograd Region. The determination of the avidicity index could establish that in the convalescents' sera, the avidicity index of virus-specific IgG was much higher than that in the patients' sera in the acute phase of infection. In relation to heteroantigen, the avidicity index and the positivity coefficient were substantially less than those in the reaction with homoantigen. The findings have indicated that the determination of the value of the avidicity index of virus-specific IgG and the positivity coefficient makes it possible to differentiate West Nile fever and tick-borne encephalitis with confidence on the basis of solid-phase enzyme immunoassay in determining virus-specific IgG in the sera of patients and convalescents in different regions of Russia.

[Results of the participation of 360 laboratories of Russia in the external quality assessment program for HBsAG tests].

During their first participation in the external quality assessment program (EQAP), 78-81% of the laboratories detect positive samples of control panels containing 0.125 IU/ml of HBsAg; 95-97% of them identify negative samples of the control panels. The high efficiency of EQAP was established when the results of the same laboratories that had participated in two cycles were compared. For correct detection of positive samples of the control panel, it is necessary to use disposable containers and tips for example for solutions of conjugate concentrate, tetramethylbenzidine, buffer for conjugate dilution, and citrate-phosphate solution. The ranges of 95% confidence interval were established for the individual values of CV values of the commercial preparation ILC-HBsAg in the laboratories: from 0 to 11.3% with estimated convergence and from 0 to 14.2% with estimated reproducibility. In making an intralaboratory control of the quality of HBsAg test using ILC-HBsAg, one should be guided by the test accuracy indices given in the application sheet.

[Target-cell susceptibility and lung phagocyte activity in mice with influenza virus resistance lowered by glucocorticoidal immunosuppression].

The results of the study showed that subcutaneous kenalog (Kn) lowered the resistance of mice to influenza virus (InV), as was seen by a decrease in 50% lethal dose and an increase in the degree of pulmonary tissue lesion, and the susceptibility of the lungs to InV, seen by the fact that 50% aerogenic infective dose (AID50) was significantly higher in the main group (Kn+InV) than in controls, which received Hanks solution subcutaneously (HS+InV). In vitro, 50% infective doses of InV for suspension of pulmonary and tracheal cells, characterizing their susceptibility to InV, were similar in Kn mice and controls. At the same time, lower resistance and higher degree of pulmonary inflammation noted in Kn mice after receiving a dose of InV that was much higher than an infecting one, was accompanied by the prevalence in the number as well as phagocyte and superoxide-producing activity of neutrophiles (Nph) over the same parameters for alveolar macrophages (AMph) as early as two days after receiving InV dose, vs. InV-infected controls. Evidently, one of the reasons for lower resistance to InV after Kn administration is significant disbalance between the functional activity of AMph and Nph populations. Ineffective AMph clearance of the lungs from InV and excessive number of recruited Nph and products of tissue disintegration may favor the development of respiratory failure and infectious-toxic shock, which leads to lower resistance in animals which receive Kn before InV infection.

[The influence of glucocorticoid immunosuppression on the course of experimental influenza pneumonia].

The study demonstrates the effects of kenalog (Kn), a synthetic glucocorticoid hormone, on the course of virus A/Aichi/2/68 influenza in white mice. In doses of 5 and 10 mg/kg, Kn reduced the weight of the adrenal glands, thymus and spleen, which was accompanied by decrease of the resistance to the mentioned virus, judging by LD50 decrease vs. this index in the control infected group. Besides, four days after infecting with 5 LD50 of influenza virus (IV), lung virus and interferon titers were significantly lower in mice pretreated with Kn vs. mice treated with placebo. Lung cell susceptibility to IV in vitro was identical in mice treated with Kn or placebo. In ultrathin lung sections of IV-infected mice, both experimental and control ones, there was virus budding in bronchial epithelium cells and type I and II alveolocytes. Analysis of inflammatory effusion compound in semithin lung sections 6 days after IV infection, found a substantially smaller number of mature alveolar macrophages (AM) and a bigger number of neutrophiles vs. infected controls. The authors reckon that higher mortality of mice pretreated with Kn before infecting, is caused not by enhancement of IV reproduction in target lung cells during influenza development, but by the contribution of other pathogenic factors. One of those may be increase of neutrophilic migration into the lungs; neutrophiles are more able to realize their significant destructive potential under the condition of reduction in the clearing function of AM and IV infection.

[Characteristics of the kidney functional state after a single dose of thyroxine in white rats].

A 50 mcg/100 g b.w. single dose of thyroxine was injected to non-inbred white rat males with body mass 140-180 g in conditions of 5% water and osmotic (3% solution of sodium chloride) load, then renal function was studied. This injection reduced creatinine clearance and phosphate excretion, raised nitrate and protein excretion. The kidney of the hyperthyroid animals retains ability to increase creatinine clearance in response to osmotic load. Thus, the above model demonstrates that in the absence of thyroxine renal toxicity it changes homeostatic renal functions both at the vascular-glomerular and tubular levels.

A prototype prophylactic anti-influenza preparation in aerosol form on the basis of Abies sibirica polyprenols.

This research investigates a promising antiviral compound based on polyprenols from Siberian silver fir (Abies sibirica). The physico-chemical characteristics of a preparation developed in aerosol form and an estimation of its protective efficacy against aerosol challenge of laboratory animals are presented. It is shown that (1) by using a simple ultrasonic disperser one can obtain aerosol of three formulations studied with about 70% of its mass accumulated in the size range below 1.8 microm; (2) 40-100% of aerosol particles contain preparation for different formulations; (3) after delivering under specified schedules, the preparations as developed can protect up to 100% of mice against 5 LD(50) of influenza A/Aichi/2/68 (H3N2) virus aerosol infection. Animals inhaled twice the preparation doses (which were 100 times lower than injection ones of the same efficacy) and did not exceed 10 microg/mouse. It was shown that the mode of action of this immunomodulating preparation was nonspecific stimulation of immune cells' various activities.

[Reactogenicity, safety and immunogenicity of a recombinant bivaccine against smallpox and hepatitis B in limited clinical trials]. / Reaktogennost', bezopasnost' i immunogennost' rekombinantnoi bivaktsiny protiv ospy i gepatita B v ogranichennykh klinicheskikh ispytaniiakh.

The reactogenicity of the embryonic live recombinant variola and hepatitis B bivaccine as tablets (Revax-BT) as well as its safety and immunogenicity were evaluated in clinical trials made in volunteers who had previously immunized or not with variola vaccine. A preliminary conclusion was made on a lack of side effects and drug safety in primary vaccination and been revaccination with low and high doses. Primary immunization of volunteers and as bivaccination with high doses stimulated the most pronounced immune response to the vaccine virus versus such effect observed in immunization of volunteers with low vaccine doses. Humoral immune response to HBs was observed in 75% of volunteers of both groups after as bivaccination. Such response was most pronounced in examinees immunized with low vaccine doses versus those who received high bivaccine doses. At the same time, no protective levels of humoral immunity response to HBs Ag were observed in volunteers first vaccinated.

[A new setup for the generation and studies of mono-disperse microbiological aerosols in medical-and-biological research]. / Novyi kompleks dlia polucheniia i izucheniia monodispersnykh mikrobiologicheskikh aérozolei v mediko-biologicheskikh issledovaniiakh.

A setup for the generation and studies of mono-disperse microbiological aerosols is described in the paper. Coefficients of 3 microm aerosol deposition in the respiratory tract of mice and rats were refined by using the above setup. The probability of deposition of such particles in the trachea and lungs of mice was proven to be equal to 1.2 +/- 0.1% and 2.6 +/- 0.2%, respectively. The probability for rats was equal to 3.2 +/- 0.2 and 11.8 +/- 0.9%, respectively. The distribution of deposited aerosol particles was determined by electron microscopy.