The Ras G Domain Lacks the Intrinsic Propensity to Form Dimers

Ras GTPase is a molecular switch controlling a number of cellular pathways including growth, proliferation, differentiation, and apoptosis. Recent reports indicated that Ras undergoes dimerization at the membrane surface through protein-protein interactions. If firmly established this property of Ras would require profound reassessment of a large amount of published data and modification of the Ras signaling paradigm. One proposed mechanism of dimerization involves formation of salt bridges between the two GTPase domains (G domains) leading to formation of a compact dimer as observed in Ras crystal structures. In this work, we interrogated the intrinsic ability of Ras to self-associate in solution by creating conditions of high local concentration through irreversibly tethering the two G domains together at their unstructured C-terminal tails. We evaluated possible self-association in this inverted tandem conjugate via analysis of the time-domain fluorescence anisotropy and NMR chemical shift perturbations. We did not observe the increased rotational correlation time expected for the G domain dimer. Variation of the ionic strength (to modulate stability of the salt bridges) did not affect the rotational correlation time in the tandem further supporting independent rotational diffusion of two G domains. In a parallel line of experiments to detect and map weak self-association of the G domains, we analyzed NMR chemical shifts perturbations at a number of sites near the crystallographic dimer interface. The nearly complete lack of chemical shift perturbations in the tandem construct supported a simple model with the independent G domains repelled from each other by their overall negative charge. These results lead us to the conclusion that self-association of the G domains cannot be responsible for homodimerization of Ras reported in the literature

Conformational States of Cytochrome P450 Oxidoreductase Evaluated by Förster Resonance Energy Transfer Using Ultrafast Transient Absorption Spectroscopy

NADPH-cytochrome P450 oxidoreductase (CYPOR) was shown to undergo large conformational rearrangements in its functional cycle. Using a new Förster resonance energy transfer (FRET) approach based on femtosecond transient absorption spectroscopy (TA), we determined the donor–acceptor distance distribution in the reduced and oxidized states of CYPOR. The unmatched time resolution of TA allowed the quantitative assessment of the donor–acceptor FRET, indicating that CYPOR assumes a closed conformation in both reduced and oxidized states in the absence of the redox partner. The described ultrafast TA measurements of FRET with readily available red–infrared fluorescent labels open new opportunities for structural studies in chromophore-rich proteins and their complexes

Accounting for the characteristics of regional manufacturing industries in developing an industrial policy

© Medwell Journals, 2016.In this study, we examine the conditions and dynamics of manufacturing industries as an important part of an overall mechanism of industrial development. Based on a proposed system of indicators, we rank manufacturing industries in 81 regions of Russia according to their development level during the period between 2006 and 2013. The study applies a ranking technique based on data analysis that constructs an integrated index measuring the development levels of the manufacturing industries (Index). The technique ranks the regions in the descending order of the integrated index. The analysis suggests for the presence of significant disparities in the geographical distribution of the Russian industrial potential. This is largely due to the sole use of naturally existing growth drivers and the low efficiency of government regulation and support measures in developing the country's manufacturing industry

Improving the calculation of the cost of the construction project using BIM technology

In the scientific article the authors summarize the results of theoretical research and practical implementation in the design of residential and public buildings BIM - information modeling technology. The questions of application of digital models for control of financial expenses at all stages of project implementation in construction are considered. An attempt is made to harmonize BIM technology with the Comsol Multiphysics software package. A review of existing studies on this issue in Europe, Asia, the United States and Russia. With the participation of the authors of the article developed a set of specialized families for the system Autodesk Revit, which allow you to perform a comprehensive preliminary study of the construction site of residential buildings. The approach providing increase of efficiency of determination of estimated cost of works on construction of object of construction based on several generalized principles is offered. This innovative approach has been tested in the design of several large construction projects in the Ural region of Russia, implemented in 2017-2019. © Published under licence by IOP Publishing Ltd

Study of Förster Resonance Energy Transfer to Lipid Domain Markers Ascertains Partitioning of Semisynthetic Lipidated N-Ras in Lipid Raft Nanodomains

Cellular membranes are heterogeneous planar lipid bilayers displaying lateral phase separation with the nanometer-scale liquid-ordered phase (also known as “lipid rafts”) surrounded by the liquid-disordered phase. Many membrane-associated proteins were found to permanently integrate into the lipid rafts, which is critical for their biological function. Isoforms H and N of Ras GTPase possess a unique ability to switch their lipid domain preference depending on the type of bound guanine nucleotide (GDP or GTP). This behavior, however, has never been demonstrated in vitro in model bilayers with recombinant proteins and therefore has been attributed to the action of binding of Ras to other proteins at the membrane surface. In this paper, we report the observation of the nucleotide-dependent switch of lipid domain preferences of the semisynthetic lipidated N-Ras in lipid raft vesicles in the absence of additional proteins. To detect segregation of Ras molecules in raft and disordered lipid domains, we measured Förster resonance energy transfer between the donor fluorophore, mant, attached to the protein-bound guanine nucleotides, and the acceptor, rhodamine-conjugated lipid, localized into the liquid-disordered domains. Herein, we established that N-Ras preferentially populated raft domains when bound to mant-GDP, while losing its preference for rafts when it was associated with a GTP mimic, mant-GppNHp. At the same time, the isolated lipidated C-terminal peptide of N-Ras was found to be localized outside of the liquid-ordered rafts, most likely in the bulk-disordered lipid. Substitution of the N-terminal G domain of N-Ras with a homologous G domain of H-Ras disrupted the nucleotide-dependent lipid domain switch

Accounting for the characteristics of regional manufacturing industries in developing an industrial policy

© Medwell Journals, 2016.In this study, we examine the conditions and dynamics of manufacturing industries as an important part of an overall mechanism of industrial development. Based on a proposed system of indicators, we rank manufacturing industries in 81 regions of Russia according to their development level during the period between 2006 and 2013. The study applies a ranking technique based on data analysis that constructs an integrated index measuring the development levels of the manufacturing industries (Index). The technique ranks the regions in the descending order of the integrated index. The analysis suggests for the presence of significant disparities in the geographical distribution of the Russian industrial potential. This is largely due to the sole use of naturally existing growth drivers and the low efficiency of government regulation and support measures in developing the country's manufacturing industry

Accounting for the characteristics of regional manufacturing industries in developing an industrial policy

© Medwell Journals, 2016.In this study, we examine the conditions and dynamics of manufacturing industries as an important part of an overall mechanism of industrial development. Based on a proposed system of indicators, we rank manufacturing industries in 81 regions of Russia according to their development level during the period between 2006 and 2013. The study applies a ranking technique based on data analysis that constructs an integrated index measuring the development levels of the manufacturing industries (Index). The technique ranks the regions in the descending order of the integrated index. The analysis suggests for the presence of significant disparities in the geographical distribution of the Russian industrial potential. This is largely due to the sole use of naturally existing growth drivers and the low efficiency of government regulation and support measures in developing the country's manufacturing industry

Accounting for the characteristics of regional manufacturing industries in developing an industrial policy

© Medwell Journals, 2016.In this study, we examine the conditions and dynamics of manufacturing industries as an important part of an overall mechanism of industrial development. Based on a proposed system of indicators, we rank manufacturing industries in 81 regions of Russia according to their development level during the period between 2006 and 2013. The study applies a ranking technique based on data analysis that constructs an integrated index measuring the development levels of the manufacturing industries (Index). The technique ranks the regions in the descending order of the integrated index. The analysis suggests for the presence of significant disparities in the geographical distribution of the Russian industrial potential. This is largely due to the sole use of naturally existing growth drivers and the low efficiency of government regulation and support measures in developing the country's manufacturing industry