Human prothymosin α inhibits division of yeast Saccharomyces cerevisiae cells, while its mutant lacking nuclear localization signal does not

AbstractEffect of human prothymosin α and its mutant over-produced in S. cerevisiae on yeast cell division was studied. Wild-type prothymosin α appeared to block division of yeast cells. Its inhibitory action could be abolished by deletion of the last nine carboxy-terminal amino acids of prothymosin α containing nuclear localization signal, thus pointing to the nucleus as a compartment, where prothymosin α performs its action

Trajectories of the internal control system in the management of agricultural organizations

Purpose: The article aims to investigate the current situation of the agricultural sector, as well as its normative-legal regulation in the Russian Federation. Currently, in the context of the economic development, the importance of the agricultural sector is undeniable. Design/Methodology/Approach: It is necessary to determine the trajectory of the internal control system in the management of agricultural organizations, to investigate the current situation of the agricultural sector in the Russian Federation, as well as to systematize the normative regulation in the agricultural sector and to identify the groups of problems of the internal control system. Findings: The article presents the stages of the implementation of the state policy in the field of a sustainable development of rural areas. There are identified the main directions of the development of the agricultural sector. Having analyzed the industry features in agriculture, determined by different scientists and practitioners, the authors identified features that affect the organization of the internal control system. There are analyzed and allocated enlarged groups of problems of internal control system in the agricultural organizations: normative-legal; organizational-methodical; informational; methodological; software and hardware. Practical Implications: The results of the study can be implemented into the practice of organization, functioning and improvement of the internal control system of agricultural organizations. Originality/Value: The main contribution of this study is to clarify and develop the theoretical and methodological aspects of the internal control system in agricultural organizations in the context of digitalization.peer-reviewe

Cost management of a construction company based on functional cost analysis

In conditions of environmental instability and uncertainty, one of the factors for the effective functioning and development of a construction company is high-quality and continuous cost management. The cost management process is aimed at maximizing profits by increasing the efficiency of the use of all resources. It requires constant monitoring to make adjustments to the planned costs and their amounts. Cost management is impossible without careful analysis. Along with the traditional methods of cost management, it is advisable for construction companies to apply functional cost analysis, which is an effective tool for optimizing costs and the quality of production functions performance. The research studies a construction company. Particular attention in the study is paid to indirect costs due to an increase in their share in the structure of the construction products cost. Within the framework of the functional cost analysis, an ABC analysis was carried out and a Pareto curve was modelled. It allowed us to focus on the allocated cost areas and classify the processes into main, basic and supportive ones. The significance of the identified processes was determined using the paired comparisons method. The results obtained allow us to draw a conclusion about the correspondence of the share of cost items and their significance for the analyzed construction company. The research materials are of interest and practical importance for the CEOs of construction companies

Early Alteration of Nucleocytoplasmic Traffic Induced by Some RNA Viruses

AbstractA HeLa cell line expressing the green fluorescent protein fused to the SV40 T-antigen nuclear localization signal (EGFP-NLS) was established. Fluorescence in these cells was confined to the nuclei. After poliovirus infection, cytoplasmic fluorescence in a proportion of cells could be detected by 1 h postinfection (p.i.) and in virtually all of the fluorescent cells by 2 h p.i. The relocation could be prevented by cycloheximide but not by inhibition of poliovirus replication by guanidine · HCl. Nuclear exit of a protein composed of three copies of GFP fused to the NLS also occurred upon poliovirus infection. A similar redistribution of EGFP-NLS took place upon infection with coxsakievirus B3 and, to a lesser extent, with vesicular stomatitis virus. The EGFP-NLS efflux was not due to the loss of NLS. Thus, some positive-strand and negative-strand RNA viruses trigger a rapid nonspecific relocation of nuclear proteins

Prothymosin α fragmentation in apoptosis

AbstractWe observed fragmentation of an essential proliferation-related human nuclear protein prothymosin α in the course of apoptosis induced by various stimuli. Prothymosin α cleavage occurred at the DDVD99 motif. In vitro, prothymosin α could be cleaved at D99 by caspase-3 and -7. Caspase hydrolysis disrupted the nuclear localization signal of prothymosin α and abrogated the ability of the truncated protein to accumulate inside the nucleus. Prothymosin α fragmentation may therefore be proposed to disable intranuclear proliferation-related function of prothymosin α in two ways: by cleaving off a short peptide containing important determinants, and by preventing active nuclear uptake of the truncated protein

Common conformational changes induced in type 2 picornavirus IRESs by cognate trans-acting factors

Type 2 internal ribosomal entry sites (IRESs) of encephalomyocarditis virus (EMCV), foot-and-mouth disease virus (FMDV) and other picornaviruses comprise five major domains H-L. Initiation of translation on these IRESs begins with specific binding of the central domain of initiation factor, eIF4G to the J-K domains, which is stimulated by eIF4A. eIF4G/eIF4A then restructure the region of ribosomal attachment on the IRES and promote recruitment of ribosomal 43S pre-initiation complexes. In addition to canonical translation factors, type 2 IRESs also require IRES trans-acting factors (ITAFs) that are hypothesized to stabilize the optimal IRES conformation that supports efficient ribosomal recruitment: the EMCV IRES is stimulated by pyrimidine tract binding protein (PTB), whereas the FMDV IRES requires PTB and ITAF45. To test this hypothesis, we assessed the effect of ITAFs on the conformations of EMCV and FMDV IRESs by comparing their influence on hydroxyl radical cleavage of these IRESs from the central domain of eIF4G. The observed changes in cleavage patterns suggest that cognate ITAFs promote similar conformational changes that are consistent with adoption by the IRESs of comparable, more compact structures, in which domain J undergoes local conformational changes and is brought into closer proximity to the base of domain I

Unidirectional constant rate motion of the ribosomal scanning particle during eukaryotic translation initiation

According to the model of translation initiation in eukaryotes, the 40S ribosomal subunit binds to capped 5′-end of mRNA and subsequently migrates along 5′-UTR in searching for initiation codon. However, it remains unclear whether the migration is the result of a random one-dimensional diffusion, or it is an energy-driven unidirectional movement. To address this issue, the method of continuous monitoring of protein synthesis in situ was used for high precision measurements of the times required for translation of mRNA with 5′-UTRs of different lengths and structures in mammalian and plant cell-free systems. For the first time, the relationship between the scanning time and the 5′-UTR length was determined and their linear correlation was experimentally demonstrated. The conclusion is made that the ribosome migration is an unidirectional motion with the rate being virtually independent of a particular mRNA sequence and secondary structure

Differential contribution of the m7G-cap to the 5′ end-dependent translation initiation of mammalian mRNAs

Many mammalian mRNAs possess long 5′ UTRs with numerous stem-loop structures. For some of them, the presence of Internal Ribosome Entry Sites (IRESes) was suggested to explain their significant activity, especially when cap-dependent translation is compromised. To test this hypothesis, we have compared the translation initiation efficiencies of some cellular 5′ UTRs reported to have IRES-activity with those lacking IRES-elements in RNA-transfected cells and cell-free systems. Unlike viral IRESes, the tested 5′ UTRs with so-called ‘cellular IRESes’ demonstrate only background activities when placed in the intercistronic position of dicistronic RNAs. In contrast, they are very active in the monocistronic context and the cap is indispensable for their activities. Surprisingly, in cultured cells or cytoplasmic extracts both the level of stimulation with the cap and the overall translation activity do not correlate with the cumulative energy of the secondary structure of the tested 5′ UTRs. The cap positive effect is still observed under profound inhibition of translation with eIF4E-BP1 but its magnitude varies for individual 5′ UTRs irrespective of the cumulative energy of their secondary structures. Thus, it is not mandatory to invoke the IRES hypothesis, at least for some mRNAs, to explain their preferential translation when eIF4E is partially inactivated

О природе изменения эффективного поверхностного заряда на кристаллах InAs при выращивании анодного оксидного слоя

Dynamics of changes in fluorine atoms distribution through grown anodic oxide layer thickness and the effective surface charge on InAs crystals under such layers has been studied. Anodic oxidation was performed in alkaline electrolyte with fluorochemical additive component in galvanostatic mode at anode current densities 0.05 or 0.5 mA·cm−2. The layers thickness in boundes 32—51 nm varied by electrodes final voltage setting in range 15—25 V. The layer thickness and refractive index was measured by ellipsometric method, and distribution of fluorine atoms through thickness — by photoelectron−spectroscopy method, combined with ion etching. At the same time, based on grown layers there were produced MIS structures, and from calculation of theirs capacitance−voltage characteristics are determined effective surface charge and surface states density, corresponding to different layer thicknesses.Main results are reduced to the facts during layers growing despite of anodizing current density comes their sealing, the profile of fluorine atoms distribution shifts towards InAs, positive effective surface charge gradually decreases from 3.6 · 1011 to 2.0 · 1011 cm−2 at surface states density in (6—7) · 1011 eV·cm−2 range for all cases. Based on comparison of these data and theoretical concepts of MIS structure charge construction, there was made a conclusion about gradual built−in charge distancing from the border with InAs in the process of growing anodic oxide layer, which explains observed effective surface charge decrease during layer thickness increasing. This results indicates that the layer growth rate exceeds the built−in charge displacement rate towards InAs.Изучена динамика изменения распределения атомов фтора по толщине выращенных слоев анодного оксида и эффективного поверхностного заряда на кристаллах InAs под такими слоями. Анодное окисление проведено в щелочном электролите с добавкой фторосодержащего компонента в гальваностатическом режиме при плотностях анодного тока 0,05 или 0,5 мА · см−2. Толщину слоев в пределах 32—51 нм варьировали, задавая конечное напряжение на электродах при выращивании в пределах значений 15—25 В. Толщина и коэффициент преломления слоев измерены методом эллипсометрии, а распределение атомов фтора по толщине — методом фотоэлектронной спектроскопии в сочетании с ионным травлением. Параллельно на основе выращенных слоев изготовлены МДП−структуры, из расчета вольт−фарадных характеристик которых определены значения эффективного поверхностного заряда и плотности поверхностных состояний, соответствующие различным толщинам слоя.Установлено, что по мере роста слоев независимо от плотности тока анодирования происходит их уплотнение. Профиль распределения атомов фтора смещается в сторону InAs, а положительный эффективный поверхностный заряд постепенно уменьшается от 3,6 · 1011 до 2,0 · 1011 см−2 при плотности поверхностных состояний в пределах (6—7) · 1011 эВ−1 · см−2 для всех случаев. На основе сопоставления полученных данных с теоретическими представлениями о зарядовом строении МДП−структуры сделан вывод о постепенном отдалении встроенного заряда от границы с InAs в процессе выращивания анодного оксидного слоя. Это объясняет наблюдаемое уменьшения эффективного поверхностного заряда с ростом толщины слоя. Полученный результат свидетельствует о том, что скорость роста слоя превышает скорость смещения встроенного заряда в сторону InAs