Adenine and guanine recognition of stop codon is mediated by different N domain conformations of translation termination factor eRF1

Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing stop signal UAA/UAAA and a photoactivatable cross-linker at definite locations. The human eRF1 peptides cross-linked to these analogs were identified. Cross-linkers on the adenines at the 2nd, 3rd or 4th position modified eRF1 near the conserved YxCxxxF loop (positions 125–131 in the N domain), but cross-linker at the 4th position mainly modified the tripeptide 26-AAR-28. This tripeptide cross-linked also with derivatized 3′-phosphate of UAA, while the same cross-linker at the 3′-phosphate of UAAA modified both the 26–28 and 67–73 fragments. A comparison of the results with those obtained earlier with mRNA analogs bearing a similar cross-linker at the guanines indicates that positioning of eRF1 toward adenines and guanines of stop signals in the 80S termination complex is different. Molecular modeling of eRF1 in the 80S termination complex showed that eRF1 fragments neighboring guanines and adenines of stop signals are compatible with different N domain conformations of eRF1. These conformations vary by positioning of stop signal purines toward the universally conserved dipeptide 31-GT-32, which neighbors guanines but is oriented more distantly from adenines

Analysis of Chemical Composition and Physical and Mechanical Properties of Power Plant Ash for its Further Processing

The results of the study of ash of Tomsk Power Plant 2 (Toms, Russia) are represented. The grain size composition of ash and distribution of main oxides among fractions have been determined. Physical and mechanical properties and quality indices of ash have been investigated. It has been established that ash of Tomsk Power Plant 2 is referred to a latent active group of cindery waste and can be used as a binding material, in fly ash aggregate productions and in highway engineering

Tendencies and prospects of tourism industry in Russia : sociological analysis of stereotypes among population during tourism trips

This article deals with the current problem – development of cultural and educational tourism industry. The information for the study was collected from the questionnaires of population of municipal districts of Russia, from the information provided by the Federal Service of State Statistics, and the results of the surveys conducted by the Russian Public Opinion Research Center (VCIOM), etc. In the course of the study, the authors revealed that the diverge social groups of the Russian society perceive Russian cultural and educational potential, tourism service in the cities in a different way; the tendencies and basic principles of domestic tourism industry have been revealed. In the article the authors defined direct dependence between weak developed domestic infrastructure and stagnation of domestic tourism industry. The results of the study showed the stereotypes which tourists follow while choosing destinations for their trips. These stereotypes may be divided into the following groups: price, comfort, climate. They range in different social groups that lead to the market fluctuation of the domestic tourism industry.peer-reviewe

In Vitro Reconstitution of Eukaryotic Translation Reveals Cooperativity between Release Factors eRF1 and eRF3

SummaryEukaryotic translation termination is triggered by peptide release factors eRF1 and eRF3. Whereas eRF1 recognizes all three termination codons and induces hydrolysis of peptidyl tRNA, eRF3's function remains obscure. Here, we reconstituted all steps of eukaryotic translation in vitro using purified ribosomal subunits; initiation, elongation, and termination factors; and aminoacyl tRNAs. This allowed us to investigate termination using pretermination complexes assembled on mRNA encoding a tetrapeptide and to propose a model for translation termination that accounts for the cooperative action of eRF1 and eRF3 in ensuring fast release of nascent polypeptide. In this model, binding of eRF1, eRF3, and GTP to pretermination complexes first induces a structural rearrangement that is manifested as a 2 nucleotide forward shift of the toeprint attributed to pretermination complexes that leads to GTP hydrolysis followed by rapid hydrolysis of peptidyl tRNA. Cooperativity between eRF1 and eRF3 required the eRF3 binding C-terminal domain of eRF1

GTP-dependent structural rearrangement of the eRF1:eRF3 complex and eRF3 sequence motifs essential for PABP binding

Translation termination in eukaryotes is governed by the concerted action of eRF1 and eRF3 factors. eRF1 recognizes the stop codon in the A site of the ribosome and promotes nascent peptide chain release, and the GTPase eRF3 facilitates this peptide release via its interaction with eRF1. In addition to its role in termination, eRF3 is involved in normal and nonsense-mediated mRNA decay through its association with cytoplasmic poly(A)-binding protein (PABP) via PAM2-1 and PAM2-2 motifs in the N-terminal domain of eRF3. We have studied complex formation between full-length eRF3 and its ligands (GDP, GTP, eRF1 and PABP) using isothermal titration calorimetry, demonstrating formation of the eRF1:eRF3:PABP:GTP complex. Analysis of the temperature dependence of eRF3 interactions with G nucleotides reveals major structural rearrangements accompanying formation of the eRF1:eRF3:GTP complex. This is in contrast to eRF1:eRF3:GDP complex formation, where no such rearrangements were detected. Thus, our results agree with the established active role of GTP in promoting translation termination. Through point mutagenesis of PAM2-1 and PAM2-2 motifs in eRF3, we demonstrate that PAM2-2, but not PAM2-1 is indispensible for eRF3:PABP complex formation

Creation of innovative solutions for the production of composite vegetable oils balanced in fatty acid composition

The problem of imbalance of PUFA in a diet of people is investigated. It is proposed to use perspective vegetable sources of oilseeds. Considered the composition and properties of products of processing of vegetable materials of the Russian, which includes ω-3 PUFA. On this basis, the prospects for the use of PUFA in food production are determine

Interrelation of social and psychological adaptation and tendency to deviant behavior of students

© Canadian Center of Science and Education. The tendency to deviant behavior of students is a negatively affecting factor to the success of their socialization. Its actualization can lead to serious consequences, and become the reason of personality degradation even its death. Some reasons of the tendency to deviant behavior are violations of social and psychological adaptation. The interrelation of positive and negative factors of social and psychological adaptation with the tendency to various forms of deviant behavior is studied in this research. It is established that students' positive elements of social and psychological adaptation, such as high adaptation, self-acceptance and acceptance of others, internal control negatively effect on possibilities of the tendency development to various forms of deviant behavior. As for negative elements of social and psychological adaptation, such as disadaptation, self-unacceptance and unacceptance of others, emotional discomfort, external control and escapism can lead to strengthening of the tendency to deviant behavior. Positive and negative elements of social and psychological adaptation on the tendency to deviant behavior of students-boys are much lower than that of students-girls

Extracts of Feijoa Inhibit Toll-Like Receptor 2 Signaling and Activate Autophagy Implicating a Role in Dietary Control of IBD

Inflammatory bowel disease (IBD) is a heterogeneous chronic inflammatory disease affecting the gut with limited treatment success for its sufferers. This suggests the need for better understanding of the different subtypes of the disease as well as nutritional interventions to compliment current treatments. In this study we assess the ability of a hydrophilic feijoa fraction (F3) to modulate autophagy a process known to regulate inflammation, via TLR2 using IBD cell lines

Ethnic and religious aspects of gender behavior and reproductive directions of young adult females living in Transbaikal region: a 10-year trend

The design of the research: two cross-sectional cohort studies with 10-year interval. The study included young adult females, 18-25 years of age: 209 women from Buryat population (in 2005 - 100, in 2015 - 109 persons) and 207 women from Russian population (in 2005 - 100, in 2015 -107 females). We found some positive trends in reproductive paradigm and gender behavior: relatively stable age of sexual debut, increasing role of health workers in young people reproductive education, a change of orientation in reproductive paradigm towards the model of multiple children family. The number of Orthodox believers significantly increased in Russian subpopulation