USING THE METHODS OF SYSTEMS BIOLOGY FOR PREDICTING PERSPECTIVE TARGET GENES TO SELECT C3 AND C4 CEREALS FOR OXIDATIVE STRESS RESISTANCE

Reactive oxygen species (ROS) are some of the most damaging factors for living systems. Cells produce ROS during normal metabolism reactions, but ROS production increases under stressful conditions. Improving the antioxidant system in cultivated plants will increase their tolerance to abiotic stresses, such as salinity, drought and cold. However, the biochemical components of the system are redundant, for each reaction is catalyzed by a series of enzymes encoded by different genes. Choosing the most perspective components of this system will help speed up evaluating the optimal breeding strategy for improving abiotic stress tolerance in economically valuable plants. In the present research article, we present the results of an integrative analysis of evolution- and expressionrelated characteristics. The work was carried out on a series of genes that belong to 4 functional groups (APX, GPX, SOD and CAT) of enzymatic components of the antioxidant defense system in six species of C3 cereal plants and 3 species of C4 cereal plants. As a result, 25 groups of orthologous genes were evaluated and described. The highest gene expression level and the greatest pressure of purifying selection were found to characterize six groups. These genes were chosen for further verification and use in breeding. Because these genes undergo the most conservative evolution and have the highest level of mRNA expression, we may assume that they contribute a lot to the antioxidant system functioning of the C3 and C4 cereal plants studied. We have shown that the integration of evolutionary characteristics and expression data represents a promising approach to predict target genes for plant breeding

FIRST DATA ON THE CONCENTRATIONS AND DISTRIBUTION OF NOBLE METALS IN NI-CU SULFIDE ORES OF THE SOUTH MAKSUT DEPOSIT (EAST KAZAKHSTAN)

The magmatic sulfide deposits in the Central Asian orogenic belt are hosted in a series of mafic–ultramafic intrusions in the Maksut zone (E Kazakhstan), the Kalatongke and the Huangshan zones in Xinjiang (NW China) and the Hongqiling zone in NE China. In the Maksut zone there are several intrusions, the best studied from which is the South Maksut intrusion with Cu–Ni–PGE mineralization.The magmatic sulfide deposits in the Central Asian orogenic belt are hosted in a series of mafic–ultramafic intrusions in the Maksut zone (E Kazakhstan), the Kalatongke and the Huangshan zones in Xinjiang (NW China) and the Hongqiling zone in NE China. In the Maksut zone there are several intrusions, the best studied from which is the South Maksut intrusion with Cu–Ni–PGE mineralization

LEAF HAIRINESS IN POTATO Solanum tuberosum: MORPHOLOGY, FUNCTION AND METHODS OF ANALYSIS

Pubescence is one of the important biotic factors in plants related to protection from stressful environmental factors. In potato, the interest in the study of pubescence is associated primarily with the fact that it plays a significant role in the protection of plants from insect pests. The review focuses on the functional role and genetic control of leaf pubescence in potato. The review describes morphological features of pubescence of potatoes, which consists of simple and glandular trichomes of several types. The ratio of trichomes of different types in potato species potato is diverse, especially for wild species. Therefore, the pubescence may serve as a classifying trait. The role of trichomes as “factories” of secondary metabolites of potatoes, among which are the esters of sucrose and terpene derivatives that serve as insect repellents. Trichomes also synthesize polyphenol oxidases, which lead to the biosynthesis of compounds which are harmful to the insects. The review presents information about the currently known genes responsible for pubescence. These are genes involved in the formation of a complex of MYB-bHLH-WD40, which controls the differentiation and development of trichomes in plants. The proteins of this complex in potatoes are primarily studied in connection with the regulation of the biosynthesis of anthocyanins. The fundamental basis for identification of genes controlling pubescence in potato is currently sequence data from complete genome sequencing. By analysis of homology with the genes of model organisms, it allows candidate genes that control important traits in potato to be identified. Work in this direction is already underway, but at the initial stage. In the final section, the review describes the methods ofphenotyping trichomes, based on the visual analysis of microscopic images (obtained both with optical and electron microscopes). The urgency of developing new high-performance approaches to the study of the morphology of the trait in potatoes has been demonstrated

Wheat leaf epidermal pattern as a model for studying the influence of stress conditions on morphogenesis

The leaf epidermis of a monocotyledonous plant is a widely used model system for studying the differentiation of plant cells, as it contains readily observable specialized cells. The approach proposed in this paper uses a growing cereal leaf to study stress-induced dynamic changes in morphogenesis. In the process of formation, the linear leaf of wheat remains in the stationary growth phase for long. This fact permits us to observe a series of successive morphogenetic events recorded in the cellular structure of the mature leaf. In studying the cellular architecture of the wheat leaf epidermis, we obtained and processed confocal 3D images of wheat leaves stained with fluorescent dyes. This procedure allows an accurate morphometric description and determination of quantitative characteristics of the leaf epidermal pattern. Low temperatures are among the factors limiting the growing of crop plants in the temperate zone. In the present work, we show significant aberrations of stomatal morphogenesis in the epidermis of boot leaves of wheat varieties Saratovskaya 29 and Yanetskis Probat in response to cold stress. We found that nonfunctional stomata predominated in the zone of maximum manifestation of stress, whereas in the zones formed before and after the stress impact, the developmental anomalies come to the disturbance in the morphogenesis of subsidiary cells. In Saratovskaya 29, a significant amount of ectopic trichomes formed in rows predetermined to stoma formation. The proposed approach can provide standardized qualitative and quantitative data on stress-induced morphogenesis aberrations in wheat leaf epidermis. Subsequently, these data can be used for verification of computer models of leaf morphogenesis. Further study of the mechanisms of the effect of cold stress on morphogenesis will add to the search for additional opportunities to increase wheat yields in areas of risky agriculture

A protocol for analysis of the quantitative characteristics of leaf pubescence in potato

Plant leaf pubescence is one of the important features, which is responsible for microclimate formation near the epidermis. It is involved in protection against adverse biotic and abiotic environmental factors. In Solanaceae, to which belongs the potato Solanum tuberosum L., leaf pubescence appears as multicellular unbranched trichomes of diverse size and morphology. Pubescence of this plants promotes resistance to insect pests, in particular, Colorado potato beetle and aphid, which is a carrier of viral diseases. During the process of breeding and genetic experiments, there is a need to assess the intensity of leaf pubescence of potato plants. For this task, micrographs taken under a microscope are commonly used. They are used to count different types of trichomes on the leaf surface to characterize the intensity of potato leaf pubescence. This approach requires visual counting of trichomes under a microscope and is fairly laborious. This protocol describes a rapid technology for quantitative assessment of the characteristics of potato pubescence (the number of trichomes on the leaf surface and the average length of trichomes) to solve the problems of genetics and breeding of this plant. It consists of a preparation technology, digital imaging of leaf folds with an optical microscope in transmitted light and subsequent automatic processing of images using the LHDetect2 software

The evolution of gene regulatory networks controlling Arabidopsis thaliana L. trichome development

Abstract Background The variation in structure and function of gene regulatory networks (GRNs) participating in organisms development is a key for understanding species-specific evolutionary strategies. Even the tiniest modification of developmental GRN might result in a substantial change of a complex morphogenetic pattern. Great variety of trichomes and their accessibility makes them a useful model for studying the molecular processes of cell fate determination, cell cycle control and cellular morphogenesis. Nowadays, a large number of genes regulating the morphogenesis of A. thaliana trichomes are described. Here we aimed at a study the evolution of the GRN defining the trichome formation, and evaluation its importance in other developmental processes. Results In study of the evolution of trichomes formation GRN we combined classical phylogenetic analysis with information on the GRN topology and composition in major plants taxa. This approach allowed us to estimate both times of evolutionary emergence of the GRN components which are mainly proteins, and the relative rate of their molecular evolution. Various simplifications of protein structure (based on the position of amino acid residues in protein globula, secondary structure type, and structural disorder) allowed us to demonstrate the evolutionary associations between changes in protein globules and speciations/duplications events. We discussed their potential involvement in protein-protein interactions and GRN function. Conclusions We hypothesize that the divergence and/or the specialization of the trichome-forming GRN is linked to the emergence of plant taxa. Information about the structural targets of the protein evolution in the GRN may predict switching points in gene networks functioning in course of evolution. We also propose a list of candidate genes responsible for the development of trichomes in a wide range of plant species

FIRST DATA ON THE CONCENTRATIONS AND DISTRIBUTION OF NOBLE METALS IN NI-CU SULFIDE ORES OF THE SOUTH MAKSUT DEPOSIT (EAST KAZAKHSTAN)

The magmatic sulfide deposits in the Central Asian orogenic belt are hosted in a series of mafic–ultramafic intrusions in the Maksut zone (E Kazakhstan), the Kalatongke and the Huangshan zones in Xinjiang (NW China) and the Hongqiling zone in NE China. In the Maksut zone there are several intrusions, the best studied from which is the South Maksut intrusion with Cu–Ni–PGE mineralization

COMPUTER APPROACHES TO WHEAT HIGH-THROUGHPUT PHENOTYPING

The growing need for rapid and accurate approaches for large-scale assessment of phenotypic characters in plants becomes more and more obvious in the studies looking into relationships between genotype and phenotype. This need is due to the advent of high throughput methods for analysis of genomes. Nowadays, any genetic experiment involves data on thousands and dozens of thousands of plants. Traditional ways of assessing most phenotypic characteristics (those with reliance on the eye, the touch, the ruler) are little effective on samples of such sizes. Modern approaches seek to take advantage of automated phenotyping, which warrants a much more rapid data acquisition, higher accuracy of the assessment of phenotypic features, measurement of new parameters of these features and exclusion of human subjectivity from the process. Additionally, automation allows measurement data to be rapidly loaded into computer databases, which reduces data processing time.In this work, we present the WheatPGE information system designed to solve the problem of integration of genotypic and phenotypic data and parameters of the environment, as well as to analyze the relationships between the genotype and phenotype in wheat. The system is used to consolidate miscellaneous data on a plant for storing and processing various morphological traits and genotypes of wheat plants as well as data on various environmental factors. The system is available at www.wheatdb.org. Its potential in genetic experiments has been demonstrated in high-throughput phenotyping of wheat leaf pubescence

FIRST DATA ON THE CONCENTRATIONS AND DISTRIBUTION OF NOBLE METALS IN NI-CU SULFIDE ORES OF THE SOUTH MAKSUT DEPOSIT (EAST KAZAKHSTAN)

The magmatic sulfide deposits in the Central Asian orogenic belt are hosted in a series of mafic–ultramafic intrusions in the Maksut zone (E Kazakhstan), the Kalatongke and the Huangshan zones in Xinjiang (NW China) and the Hongqiling zone in NE China. In the Maksut zone there are several intrusions, the best studied from which is the South Maksut intrusion with Cu–Ni–PGE mineralization

Combined in silico/in vivo analysis of mechanisms providing for root apical meristem self-organization and maintenance

BACKGROUND AND AIMS: The root apical meristem (RAM) is the plant stem cell niche which provides for the formation and continuous development of the root. Auxin is the main regulator of RAM functioning, and auxin maxima coincide with the sites of RAM initiation and maintenance. Auxin gradients are formed due to local auxin biosynthesis and polar auxin transport. The PIN family of auxin transporters plays a critical role in polar auxin transport, and two mechanisms of auxin maximum formation in the RAM based on PIN-mediated auxin transport have been proposed to date: the reverse fountain and the reflected flow mechanisms. METHODS: The two mechanisms are combined here in in silico studies of auxin distribution in intact roots and roots cut into two pieces in the proximal meristem region. In parallel, corresponding experiments were performed in vivo using DR5::GFP Arabidopsis plants. KEY RESULTS: The reverse fountain and the reflected flow mechanism naturally cooperate for RAM patterning and maintenance in intact root. Regeneration of the RAM in decapitated roots is provided by the reflected flow mechanism. In the excised root tips local auxin biosynthesis either alone or in cooperation with the reverse fountain enables RAM maintenance. CONCLUSIONS: The efficiency of a dual-mechanism model in guiding biological experiments on RAM regeneration and maintenance is demonstrated. The model also allows estimation of the concentrations of auxin and PINs in root cells during development and under various treatments. The dual-mechanism model proposed here can be a powerful tool for the study of several different aspects of auxin function in root