Ancient origin, functional conservation and fast evolution of DNA-dependent RNA polymerase III

RNA polymerase III contains seventeen subunits in yeasts (Saccharomyces cerevisiae and Schizosaccharomyces pombe) and in human cells. Twelve of them are akin to the core RNA polymerase I or II. The five other are RNA polymerase III-specific and form the functionally distinct groups Rpc31-Rpc34-Rpc82 and Rpc37-Rpc53. Currently sequenced eukaryotic genomes revealed significant homology to these seventeen subunits in Fungi, Animals, Plants and Amoebozoans. Except for subunit Rpc31, this also extended to the much more distantly related genomes of Alveolates and Excavates, indicating that the complex subunit organization of RNA polymerase III emerged at a very early stage of eukaryotic evolution. The Sch.pombe subunits were expressed in S.cerevisiae null mutants and tested for growth. Ten core subunits showed heterospecific complementation, but the two largest catalytic subunits (Rpc1 and Rpc2) and all five RNA polymerase III-specific subunits (Rpc82, Rpc53, Rpc37, Rpc34 and Rpc31) were non-functional. Three highly conserved RNA polymerase III-specific domains were found in the twelve-subunit core structure. They correspond to the Rpc17-Rpc25 dimer, involved in transcription initiation, to an N-terminal domain of the largest subunit Rpc1 important to anchor Rpc31, Rpc34 and Rpc82, and to a C-terminal domain of Rpc1 that presumably holds Rpc37, Rpc53 and their Rpc11 partner

Cooperation between Translating Ribosomes and RNA Polymerase in Transcription

International audienceDuring transcription of protein-coding genes, bacterial RNA polymerase (RNAP) is closely followed by a ribosome that translates the newly synthesized transcript. Our in vivo measurements show that the overall elongation rate of transcription is tightly controlled by the rate of translation. Acceleration and deceleration of a ribosome result in corresponding changes in the speed of RNAP. Moreover, we found an inverse correlation between the number of rare codons in a gene, which delay ribosome progression, and the rate of transcription. The stimulating effect of a ribosome on RNAP is achieved by preventing its spontaneous backtracking, which enhances the pace and also facilitates readthrough of roadblocks in vivo. Such a cooperative mechanism ensures that the transcriptional yield is always adjusted to translational needs at different genes and under various growth conditions

The Human Isoform of RNA Polymerase II Subunit hRPB11bα Specifically Interacts with Transcription Factor ATF4

Rpb11 subunit of RNA polymerase II of Eukaryotes is related to N-terminal domain of eubacterial α subunit and forms a complex with Rpb3 subunit analogous to prokaryotic α2 homodimer, which is involved in RNA polymerase assembly and promoter recognition. In humans, a POLR2J gene family has been identified that potentially encodes several hRPB11 proteins differing mainly in their short C-terminal regions. The functions of the different human specific isoforms are still mainly unknown. To further characterize the minor human specific isoform of RNA polymerase II subunit hRPB11bα, the only one from hRPB11 (POLR2J) homologues that can replace its yeast counterpart in vivo, we used it as bait in a yeast two-hybrid screening of a human fetal brain cDNA library. By this analysis and subsequent co-purification assay in vitro, we identified transcription factor ATF4 as a prominent partner of the minor RNA polymerase II (RNAP II) subunit hRPB11bα. We demonstrated that the hRPB11bα interacts with leucine b-Zip domain located on the C-terminal part of ATF4. Overexpression of ATF4 activated the reporter more than 10-fold whereas co-transfection of hRPB11bα resulted in a 2.5-fold enhancement of ATF4 activation. Our data indicate that the mode of interaction of human RNAP II main (containing major for of hRPB11 subunit) and minor (containing hRPB11bα isoform of POLR2J subunit) transcription enzymes with ATF4 is certainly different in the two complexes involving hRPB3–ATF4 (not hRPB11a–ATF4) and hRpb11bα–ATF4 platforms in the first and the second case, respectively. The interaction of hRPB11bα and ATF4 appears to be necessary for the activation of RNA polymerase II containing the minor isoform of the hRPB11 subunit (POLR2J) on gene promoters regulated by this transcription factor. ATF4 activates transcription by directly contacting RNA polymerase II in the region of the heterodimer of α-like subunits (Rpb3–Rpb11) without involving a Mediator, which provides fast and highly effective activation of transcription of the desired genes. In RNA polymerase II of Homo sapiens that contains plural isoforms of the subunit hRPB11 (POLR2J), the strength of the hRPB11–ATF4 interaction appeared to be isoform-specific, providing the first functional distinction between the previously discovered human forms of the Rpb11 subunit

Technology and Properties

Нефтяной кокс - основное сырье для производства анодов алюминиевых электролизеров. Качество кокса во многом определяет технологию, экологию и экономику производства алюминия. С точки зрения производителей алюминия, нефтяной кокс должен обладать следующими свойствами: минимальной зольностью и отсутствием каталитических примесей, высокой стойкостью к кислороду и СО2, низкой пористостью и удельным электросопротивлением, механической прочностью, приемлемой для обработки, и хорошей микроструктурой. Нефтяной кокс производят из остатков переработки нефти и вторичных нефтепродуктов. В силу особенностей технологии качество нефтяного кокса является компромиссом между получением светлых нефтепродуктов и сырья для коксования. Поэтому неудивительно, что очень небольшое количество коксов могут удовлетворить всем требованиям алюминиевой промышленности. В статье с точки зрения мирового опыта алюминиевой промышленности рассмотрены вопросы формирования свойств кокса от начала нефтепереработки до склада сырья анодного производства. Предлагаемая статья является первой в серии совместных работ сотрудников Сибирского федерального университета и специалистов Ачинского НПЗ, посвященных строительству и развитию производства нефтяного кокса на Ачинском НПЗ.Petroleum coke is the main raw material for aluminum electrolysis anodes. Quality of coke determinates the technology, ecology and economics of production of aluminum. From the aluminum producers point of view, petroleum coke should have the following characteristics: - a minimum ash content and the absence of impurities, - high resistance to oxygen and CO2, - low porosity and electrical resistivity - mechanical strength, acceptable for processing - good microstructure. Petroleum coke is produced from petroleum residues and secondary petroleum products. Because of the peculiarity of the technology, the quality of petroleum coke is a compromise between the receipt of light fuel and raw coking. It is not surprising that only a very small amount of coke can satisfy all the requirements of the aluminum industry. The purpose this article is formation of cokes properties from the beginning of oil refining up to the anode plant. The article is the first in a lot of cooperated works of the Siberian Federal University and specialists of the Achinsk refinery, dedicated to construction and development of production of petroleum coke at the Achinsk refinery

Technology and Properties

Нефтяной кокс - основное сырье для производства анодов алюминиевых электролизеров. Качество кокса во многом определяет технологию, экологию и экономику производства алюминия. С точки зрения производителей алюминия, нефтяной кокс должен обладать следующими свойствами: минимальной зольностью и отсутствием каталитических примесей, высокой стойкостью к кислороду и СО2, низкой пористостью и удельным электросопротивлением, механической прочностью, приемлемой для обработки, и хорошей микроструктурой. Нефтяной кокс производят из остатков переработки нефти и вторичных нефтепродуктов. В силу особенностей технологии качество нефтяного кокса является компромиссом между получением светлых нефтепродуктов и сырья для коксования. Поэтому неудивительно, что очень небольшое количество коксов могут удовлетворить всем требованиям алюминиевой промышленности. В статье с точки зрения мирового опыта алюминиевой промышленности рассмотрены вопросы формирования свойств кокса от начала нефтепереработки до склада сырья анодного производства. Предлагаемая статья является первой в серии совместных работ сотрудников Сибирского федерального университета и специалистов Ачинского НПЗ, посвященных строительству и развитию производства нефтяного кокса на Ачинском НПЗ.Petroleum coke is the main raw material for aluminum electrolysis anodes. Quality of coke determinates the technology, ecology and economics of production of aluminum. From the aluminum producers point of view, petroleum coke should have the following characteristics: - a minimum ash content and the absence of impurities, - high resistance to oxygen and CO2, - low porosity and electrical resistivity - mechanical strength, acceptable for processing - good microstructure. Petroleum coke is produced from petroleum residues and secondary petroleum products. Because of the peculiarity of the technology, the quality of petroleum coke is a compromise between the receipt of light fuel and raw coking. It is not surprising that only a very small amount of coke can satisfy all the requirements of the aluminum industry. The purpose this article is formation of cokes properties from the beginning of oil refining up to the anode plant. The article is the first in a lot of cooperated works of the Siberian Federal University and specialists of the Achinsk refinery, dedicated to construction and development of production of petroleum coke at the Achinsk refinery

Complex Research of Liquid Products of Delayed Coking of Heavy Petroleum Residues of “Achinsk Refinery”

Осуществлено комплексное исследование индивидуального и группового компонентного состава, физико-химических показателей жидких продуктов, образующихся при коксовании гудрона ОАО «АНПЗ ВНК» при различных температурах и давлении коксования, для оценки возможности их вовлечения в номенклатуру товарной продукции. Особое внимание уделено количественным показателям углеводородного состава дистиллятной фракции, а также оценке содержания общей и меркаптановой серы. Выявлены закономерности изменений состава и свойств узких фракций жидких продуктов коксования от технологических параметров процесса. Разработаны предварительные рекомендации по достижению максимального показателя выхода и оптимального углеводородного состава дистиллятных фракцийCarried out a comprehensive study of individual and group component composition, physical and chemical parameters of liquid products formed during coking tar of «Achinsk Refinery» at various temperatures and pressures coking in order to assess the possibility of involving them in the range of marketable products. Special attention is paid to the quantitative indicators of the hydrocarbon composition of distillate fraction, as well as evaluating the content of general and mercaptan sulfur. Revealed regularities of changes in the composition and properties of narrow fractions of liquid products of coking on the technological parameters of the process. Developed preliminary recommendations for the achievement of the maximum rate of output and optimal hydrocarbon composition of distillate fraction

Complex Research of Liquid Products of Delayed Coking of Heavy Petroleum Residues of “Achinsk Refinery”

Осуществлено комплексное исследование индивидуального и группового компонентного состава, физико-химических показателей жидких продуктов, образующихся при коксовании гудрона ОАО «АНПЗ ВНК» при различных температурах и давлении коксования, для оценки возможности их вовлечения в номенклатуру товарной продукции. Особое внимание уделено количественным показателям углеводородного состава дистиллятной фракции, а также оценке содержания общей и меркаптановой серы. Выявлены закономерности изменений состава и свойств узких фракций жидких продуктов коксования от технологических параметров процесса. Разработаны предварительные рекомендации по достижению максимального показателя выхода и оптимального углеводородного состава дистиллятных фракцийCarried out a comprehensive study of individual and group component composition, physical and chemical parameters of liquid products formed during coking tar of «Achinsk Refinery» at various temperatures and pressures coking in order to assess the possibility of involving them in the range of marketable products. Special attention is paid to the quantitative indicators of the hydrocarbon composition of distillate fraction, as well as evaluating the content of general and mercaptan sulfur. Revealed regularities of changes in the composition and properties of narrow fractions of liquid products of coking on the technological parameters of the process. Developed preliminary recommendations for the achievement of the maximum rate of output and optimal hydrocarbon composition of distillate fraction

Evaluation of the Effectiveness of Different LED Irradiators When Growing Red Mustard (Brassica juncea L.) in Indoor Farming

Investigation is devoted to the optimization of light spectrum and intensity used for red mustard growing. Notably, most of the studies devoted to red mustard growing were conducted on micro-greens, which is not enough for the development of methods and recommendations for making the right choices about the irradiation parameters for full-cycle cultivation. In this study, we tested four models of LED with different ratios of blue, green red and far red radiation intensity: 12:20:63:5; 15:30:49:6; 30:1:68:1, in two values of photon flux density (PFD)—120 and 180 µmol m−2 s−1—to determine the most effective combination for red mustard growing. The study was conducted in a container-type climate chamber, where the red leaf mustard was cultivated in hydroponics. On the 30th day of cultivation, the plant’s morphological, biochemical and chlorophyll fluorescence parameters, and reflection coefficients were recorded. The results indicated that the PFD 120 µmol m−2 s−1 had a worse effect on both mustard leaf biomass accumulation and nitrate concentration (13–30% higher) in the plants. The best lighting option for growing red mustard was the blue–red spectrum, as the most efficient in terms of converting electricity into biomass (77 Wth/g). This light spectrum contributes to plant development with a larger leaf area (60%) and a fresh mass (54%) compared with the control, which has a maximum similarity in spectrum percentage to the sunlight spectrum. The presence of green and far red radiation with the blue–red light spectrum in various proportions at the same level of PFD had a negative effect on plant fresh mass, leaf surface area and photosynthetic activity. The obtained results could be useful for lighting parameters’ optimization when growing red mustard in urban farms

Impact of Ultraviolet Radiation on the Pigment Content and Essential Oil Accumulation in Sweet Basil (Ocimum basilicum L.)

In this study, we investigated the effects of additional ultraviolet radiation (UV) on the main growth fluorescent lamp light on pigment content and essential oil accumulation in sweet basil (Ocimum basilicum L.). Three different UV light sources from light-emitting diodes and discharge lamps, which emit UV in the UV-A (315–400 nm), UV-B (280–315 nm) and UV-C (100–280 nm) ranges, were tested for basil plant growing. The plants, growing under additional UV-A and UV-B from mercury lamps, on the 60th growing day were higher than control plants by 90% and 53%, respectively. The fresh leaf mass of the UV-A irradiated basil plants was 2.4-fold higher than the control plant mass. The dry mass/fresh mass ratio of the UV-A and UV-B irradiated plants was higher by 45% and 35% in comparison to the control plants. Leaf area was increased by 40% and 20%, respectively. UV-C affected the anthocyanin content most strongly, they increased by 50%, whereas only by 27% and 0% under UV-A and UV-B. Any UV addition did not affect the essential oil total contents but altered the essential oil compositions. UV-A and UV-B increased the linalool proportion from 10% to 20%, and to 25%, respectively, in contrast to UV-C, which reduced it to 3%. UV-C induced the eugenol methyl ether accumulation (17%) and inhibited plant growth. Moreover, UV increased the proportion of α-guaiene, β-cubebene and α-bulnesene and decreased the proportion of sabinene and fenchone. Thus, we concluded that UV (except UV-C) used jointly with main light with PPFD 120 ± 10 μmol photons·m−2·s−1 for sweet basil cultivation may be justified to stimulate basil growth and optimize the essential oil accumulation