The paper presents the results of analysis of astroclimatic conditions in the Big Telescope Alt-azimuthal (BTA) region (40°N–50°N; 35°E–55°E). Using data from the European center for medium-range ...weather forecast ReAnalysis (ERA-5), we estimated the averaged spatial distributions in total cloud cover, vertical integral of mean kinetic energy, vertical component of wind speed, and wind speed shears, as well as inverse values of Richardson number 1/Ri. An extensive region with the development of atmospheric flows is formed south and southeast of BTA in winter. High inverse values of the Richardson number, spatial heterogeneities in vertical wind speed, and significant wind speed shears in the lower atmosphere are observed in this region. In terms of turbulence development over BTA, the best time for astronomical observations falls in summer, when vertical shears of wind speed are weakened in the lower atmospheric layers. The situation is opposite in the upper troposphere. In winter, BTA is in the region of moderate vertical wind shears. In summer, a region with increased vertical wind speed shears is formed. Taking into account that the intensity of optical turbulence decreases rapidly with height, better image quality can be expected in summer. Such structure of the atmosphere does not allow one to directly apply atmospheric models in order to describe turbulence based on the turbulence strength as function of its ground values, or to use the classical model describing the turbulence velocity as function of air flow velocity at the height corresponding to the 200 hPa level.
Artificial hybrids between cultivated
species and wild
that possess genes for resistance to biotic and abiotic stresses can be important for oat breeding. For the first time, a comprehensive study of ...genomes of artificial fertile hybrids
×
and their parental species was carried out based on the chromosome FISH mapping of satellite DNA sequences (satDNAs) and also analysis of intragenomic polymorphism in the 18S-ITS1-5.8S rDNA region, using NGS data. Chromosome distribution patterns of marker satDNAs allowed us to identify all chromosomes in the studied karyotypes, determine their subgenomic affiliation, and detect several chromosome rearrangements. Based on the obtained cytogenomic data, we revealed differences between two
subgenomes and demonstrated that only one of them was inherited in the studied octoploid hybrids. Ribotype analyses showed that the second major ribotype of
was species-specific and was not represented in rDNA pools of the octoploids, which could be related to the allopolyploid origin of this species. Our results indicate that the use of marker satDNAs in cytogenomic studies can provide important data on genomic relationships within
allopolyploid species and hybrids, and also expand the potential for interspecific crosses for breeding.
This article presents an experimental confirmation of the decomposition of the ultrashort pulses (USP) in three structures based on folded meander microstrip lines. It was found that additional ...folding of the folded turn allows increasing the USP attenuation. The analysis of N -norms revealed that such folding allows the probability of electrical breakdown to be additionally reduced. Besides, the likelihood of arc discharge can be decreased. Meanwhile, the probability of equipment damage increases due to the total energy of the pulse, as well as the likelihood of dielectric breakdown. The maximum USP attenuation at the output of the folded turn was 6.94 times. Simulation results show acceptable agreement with measurements. The useful signal integrity was analyzed using a source of pseudorandom binary sequences of 10 000 bits at bitrate transfer rates of 50 and 100 Mbps. Based on this analysis, we recommend to use a folded turn in conjunction with a multiblock generator with a PLL1707 phase lock. We also propose to use the folded turn in conjunction with a gas discharge device to improve protective characteristics.
The article presents the results of calculating time responses of a meander line (ML) turn to pulse excitation. The responses were calculated at the ML nodes analytically and numerically, and ...demonstrated coincidence. Besides, the created prototype of the ML turn was measured and showed good qualitative and acceptable quantitative agreement with the simulation results. Analytical models were found to be promising since they may significantly accelerate the design of such MLs in contrast to numerical methods which provide costly multivariate simulation of the time response during optimization.
Callus and suspension cell cultures were successfully developed from
Sutherlandia frutescens
(Fabaceae), an endemic medicinal plant of South Africa. Two callus cell lines, originating from hypocotyl ...and cotyledon explants of in vitro seedlings under both dark and light conditions, showed intensive fresh weight accumulation with growth index ranging from 4.6 to 5.9. Suspension cell cultures induced from two callus lines had similar growth profiles and their growth index (15–18), specific growth rate (0.15–0.16 day
−1
), productivity (0.83–0.96 g/(l day)) and maximum biomass accumulation (16–18 g/l) remained relatively high for Fabaceae cell cultures during 27 sub-cultivations. Callus and suspension cell cultures showed similar profiles of secondary metabolites that were, however, different from leaves of greenhouse plants. Isoflavones were predominant in both callus and suspension cell cultures while flavonoids (sutherlandins) and triterpene glycosides of the cycloartane group (sutherlandiosides) were mostly found in leaves. Nineteen fatty acids (FA), both short- and very-long-chained (up to C
25:0
), were found in cell cultures. Linoleic and α-linolenic FA together comprised 60–64% out of total FA content in cell cultures followed by palmitic acid (18–25%). Extracts of suspension cell biomass exhibited antimicrobial activity against
Staphylococcus aureus
but were not effective against
Pseudomonas aeruginosa.
To the best of our knowledge, this is the first report on the induction, phytochemical composition and antimicrobial activity screening of
S. frutescens
suspension cell cultures which opens the door for their biotechnological application.
Ex situ collections of algae, cyanobacteria, and plant materials (cell cultures, hairy and adventitious root cultures, shoots, etc.) maintained in vitro or in liquid nitrogen (-196 °C, LN) are ...valuable sources of strains with unique ecological and biotechnological traits. Such collections play a vital role in bioresource conservation, science, and industry development but are rarely covered in publications. Here, we provide an overview of five genetic collections maintained at the Institute of Plant Physiology of the Russian Academy of Sciences (IPPRAS) since the 1950-1970s using in vitro and cryopreservation approaches. These collections represent different levels of plant organization, from individual cells (cell culture collection) to organs (hairy and adventitious root cultures, shoot apices) to in vitro plants. The total collection holdings comprise more than 430 strains of algae and cyanobacteria, over 200 potato clones, 117 cell cultures, and 50 strains of hairy and adventitious root cultures of medicinal and model plant species. The IPPRAS plant cryobank preserves in LN over 1000 specimens of in vitro cultures and seeds of wild and cultivated plants belonging to 457 species and 74 families. Several algae and plant cell culture strains have been adapted for cultivation in bioreactors from laboratory (5-20-L) to pilot (75-L) to semi-industrial (150-630-L) scale for the production of biomass with high nutritive or pharmacological value. Some of the strains with proven biological activities are currently used to produce cosmetics and food supplements. Here, we provide an overview of the current collections' composition and major activities, their use in research, biotechnology, and commercial application. We also highlight the most interesting studies performed with collection strains and discuss strategies for the collections' future development and exploitation in view of current trends in biotechnology and genetic resources conservation.
In this article, we analyzed the origin of wild polyploid oats (Avena L., Poaceae) using the region 18S rDNA (partially)–ITS1–5.8S rDNA obtained via NGS. There are six tetraploid (2n = 28) and four ...hexaploid (2n = 42) wild species differing by specific genome combinations: A. barbata, A. vaviloviana (AB), A. agadiriana (AB or BB), A. magna, A. murphyi, A. insularis (AC or CD), A. ludoviciana, A. sterilis, A. fatua, and A. occidentalis (ACD). We compared the pool of marker sequences of polyploid oats with those of their putative diploid ancestors: A. atlantica (As-genome), A. hirtula (As), A. canariensis (Ac), A. ventricosa (Cv), and A. clauda (paleopolyploid with Cp and A-related rDNA). We found 15 major ribotypes (more than 1000 reads per rDNA pool) in polyploid oats. Comparing them, we found that the AB-tetraploid oats possibly inherited their A-genome ribotypes from A. atlantica (As1-ribotype), whereas their B-genome ribotype is specific and can be a derivative of the A-genome family. Our data do not support the hypothesis of the CD-genome set in A. magna, A. murphyi, and A. insularis: they have an AC-genome ribotype constitution instead. The C-genome-related sequences could have been obtained from A. ventricosa. Hexaploids show a different ribotype pattern than tetraploids; the main ribotypes of A. fatua, A. ludoviciana, and A. sterilis probably belong to the D-group and are also shared with one of the major ribotypes of A. clauda.
•Free Zn2+ levels regulate the expression of Zn homeostasis genes in Arabidopsis cells.•Zn deficiency influences protein folding in the cytosol of Arabidopsis cells.•mRNA degradation of Zn ...homeostasis genes is influenced by free Zn2+ levels.
Zinc is one of the most widespread transition metals in plants, and Zn deficiency has many adverse effects on plant productivity and human health. The zinc homeostasis system is actively studied; however, the mechanisms underlying regulation of Zn homeostasis have not been fully elucidated. Two potential ways to assess cellular Zn homeostasis are to sense changes in the free Zn2+ levels or disturbances in protein folding due to zinc deficiency. We found that changes in the cellular free Zn2+ level regulated the transcriptional activity of a set of primary Zn homeostasis genes in a dose-dependent manner and with fast kinetics. We propose that in addition to the well-known bZIP19/bZIP23 transcription factors, another Zn-sensing system exists in the cell and regulates free Zn2+-dependent changes in MTP2 gene expression. We first demonstrated that changes in the free Zn2+ levels in the cells likely influenced not only the transcriptional activation but also the mRNA degradation rates of Zn homeostasis genes, which were accelerated for several genes during recovery of the cellular Zn status. Zn deficiency clearly disturbed the protein folding processes in the cytosol of plant cells, but the cellular response system to these disturbances did not play a significant role in the regulation of Zn homeostasis genes.
The labile zinc pool in plant cells Zlobin, Ilya E; Kartashov, Alexander V; Nosov, Alexander V ...
Functional plant biology : FPB,
01/2019, Letnik:
46, Številka:
9
Journal Article
Recenzirano
Zinc is the most abundant and important transition metal in plants; however, the dynamic aspects of zinc homeostasis in plant cells are poorly understood. In this study we explored the pool of labile ...exchangeable zinc complexes in plant cells, and the potential influence of changes in intracellular zinc availability on cellular physiology. Work was performed on cultivated cell extracts of Arabidopsis thaliana (L.) Heynh. and Thellungiella salsuginea (Pall.) O.E. Schulz grown under control (3.48 µM Zn2+), 10-fold Zn excess or Zn starvation conditions. The free and labile Zn contents in the extracts were then determined by fluorimetric titration. We observed for the first time that plant cells contain micromolar concentrations of labile zinc complexes that account for a low percentage of the total zinc content. Labile zinc is mainly protein bound. Zn starvation inhibits cell proliferation and leads to the disappearance of the labile zinc pool, whereas Zn excess drastically increases the labile zinc pool. Free Zn2+ is buffered at picomolar concentrations in the intracellular milieu, and the increase in free Zn2+ concentrations to low nanomolar values clearly modulates enzyme activity by direct reversible binding. Such increases in free Zn2+ can be achieved by the substantial influx of additional zinc or by the oxidation of zinc-binding thiols. The observed features of the labile zinc pool in plant cells suggest it has a role in intracellular zinc trafficking and zinc signalling.
