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The discovery of new genetic editing technologies (new genetic technologies, NGT) made it possible to change the genetic material of organisms faster, easier, more accurate and cheaper. Gene modification in the laboratory has become the most promising method of creating new crops. In all developed countries possessing such technologies, including Russia, the question has been raised for a long time whether NGT should be qualified in the legal field in a different way than previously known traditional methods of genetic engineering, which have been in practice since the 1970s.The Russian and European experience of evaluating technologies in the field of NGT has been studied and summarized in order to overcome the mentioned barriers in the Russian agro-industrial sphere, solve import substitution problems, ensure the sustainable development of domestic breeding and crop production, and realize the competitive advantages available today in Russian legislation for Russian innovative firms and agricultural producers.The options of modernization of the Russian legislation are considered, which would allow to consolidate and develop the successes of domestic scientists and breeders, to make it more stable and safe to provide Russian consumers (as well as importers of Russian food abroad) with high-quality and inexpensive food products.For the first time, a comparative analysis of studies of new genetic editing technologies in the context of their industrial implementation and legal regulation, basing on analytics from leading European centers and Russian Federation institutions, was carried out.

This paper presents a phenomenological analysis of thermodynamic parameters of a pulsed supersonic gas jet in a conical nozzle. Conditions have been found out for the condensation and formation of large krypton clusters resulting from phase transitions during adiabatic expansion of gas through the nozzle into vacuum. We have identified the phase state of the large clusters (submicron droplets consisting of ∼107 monomers) forming in the jet and obtained a high yield of X-rays from a cluster nanoplasma produced by femtosecond laser pulses of relativistic intensity I. It has been shown that, at I ≈ 3 × 1018 W cm−2, a nanoplasma consisting of large krypton clusters emits a broadband X-ray spectrum in the range 5 – 100 keV. The integrated laser to X-ray energy conversion efficiency achieved is ∼10−5 (400 nJ), and the efficiency of characteristic Kα line (12.6 keV) generation is ∼1.5 × 10−6 (68 nJ), which corresponds to a quantum yield of ∼3 × 108 photons s−1 (4π)−1, with a contrast of ∼25 relative to bremsstrahlung background.

A new approach is proposed to form a jet with submicron aggregates for femtosecond laser neutron generation under nonlinear interaction with relativistically intense laser pulse. Aggregates are formed through the rapid expansion into vacuum of the supercritical mixture of CO2 + CD3OD (3:1). For the first time, fusion neutrons (2.45 MeV) with a peak output of 3 × 103 neutron/pulse/4π and efficiency of 6 × 104 neutron J−1 were obtained under interaction of Ti:Sa laser pulse having 3 × 1018 W cm−2 intensity with submicron aggregates produced from supercritical CO2 + CD3OD mixture.

The supercritical CO2 (scCO2) is widely used as solvent and transport media in different technologies. The technological aspects of scCO2 fluid applications strongly depend on spatial&ndash, temporal fluctuations of its thermodynamic parameters. The region of these parameters&rsquo, maximal fluctuations on the p-T (pressure-temperature) diagram is called Widom delta. It has significant practical and fundamental interest. We offer an approach that combines optical measurements and molecular dynamics simulation in a wide range of pressures and temperatures. We studied the microstructure of supercritical CO2 fluid and its binary mixture with ethanol in a wide range of temperatures and pressures using molecular dynamics (MD) simulation. MD is used to retrieve a set of optical characteristics such as Raman spectra, refractive indexes and molecular refraction and was verified by appropriate experimental measurements. We demonstrated that in the Widom delta the monotonic dependence of the optical properties on the CO2 density is violated. It is caused by the rapid increase of density fluctuations and medium-sized (20&ndash, 30 molecules) cluster formation. We identified the correlation between cluster parameters and optical properties of the media, in particular, it is established that the clusters in the Widom delta acts as a seed for clustering in molecular jets. MD demonstrates that the cluster formation is stronger in the supercritical CO2-ethanol mixture, where the extended binary clusters are formed, that is, the nonlinear refractive index significantly increased. The influence of the supercritical state in the cell on the formation of supersonic cluster jets is studied using the Mie scattering technique.

Phase behavior and structure formation was studied using optical interferometry, nephelometry, and refractometry in the polymer–solvent–nonsolvent system for DMF solutions of two poly(amic acids): based on 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride and meta-phenylenediamine (PAA-1) and pyromellitic acid dianhydride and 4,4′-oxydianiline (PAA-2). Distilled water and its mixtures with DMF were used as a nonsolvent. According to the results of the study, isothermal cross sections of the phase state diagram in the threecomponent system were plotted, the position of the critical point, the spinodal, and the conodes were determined, the movement of the figurative points in the system was traced depending on the nonsolvent composition.

A supersonic jet consisting of atomic clusters of noble gases under interaction with high-power femtosecond radiation allows control of the radiation pattern and efficiency of generation of terahertz (THz) radiation. The laser filament formed in this jet is spatially defined by the shape of the jet. The concentration, spatial distribution, and size of the clusters influence the propagation of the femtosecond laser pulse in it and the formation of a THz pulse. We show that a specially formed cluster jet allows the shaping of THz radiation with a high degree of directionality and increase its intensity by more than 10 times.

We present the results of experimental studies of THz emission from argon cluster nanoplasma switched by the intense femtosecond laser pulses. We have performed measurements of the angular distribution of the THz radiation emitted from the clustered nanoplasma with two polarization states of the linearly polarized laser beam. We have found that polarization state of the laser radiation may influence on the efficiency of THz generation in cluster beam.

In comparative experiments, it was found that the maximum efficiency of third harmonic generation (THG) in cluster nanoplasma was ∼9x10−5 and was approximately 4 times less effective than the case of THG in gas under similar experimental conditions. This result is consistent with theoretical calculations and show that THG amplitude in a gas is about an order of magnitude higher than in a cluster medium. The discrepancy between the THG efficiency in gas and clusters obtained theoretically and experimentally in discussed.

The I-V characteristics of high-voltage 4H-SiC diodes with a Schottky barrier ∼1.1 eV in height are measured and analyzed. The forward I-V characteristics proved to be close to “ideal” in the temperature range of 295–470 K. The reverse I-V characteristics are adequately described by the model of thermionic emission at the voltages to 2 kV in the temperature range of 361–470 K if, additionally, a barrier lowering with an increase in the band bending in the semiconductor is taken into account.

Formation of heterologous (calf thymus double-stranded DNA) and homologous (linearized pBR322 plasmid double-stranded DNA) quadruplexes upon binding with the simple aliphatic tripeptide derivative (dansyl hydrazide trivaline) was examined by fluorimetry, flow linear and circular dichroism and electron microscopy. The morphology of the rod-like compact particles formed due to the association of double-stranded DNA segments proved to be the same for both DNAs, whereas the stability of the compact DNA structure upon tripeptide removal from the complex with DNA differed substantially for homologous versus non-homologous double-stranded DNA used. The increase of NaCl concentration in the solution up to 30 mM removes the peptide from both types of the complexes completely. At the same time at 20 mM NaCl calf thymus DNA quadruplexes readily dissociate, whereas the structures formed by plasmid DNA retain their morphology in the solution containing NaCl with concentrations up to 40 mM and are only partially disrupted at even higher NaCl concentration. These results provide the analogy between trivaline-DNA model complexes and RecA-DNA binding.

It has been shown by equilibrium dialysis that at a poly(U) concentration above the "critical" one, the complete polymer saturation with trivaline reaches approximately 0.7, i.e., in these conditions the peptide dimer occupied on poly(U) a site of three bases in length. It has been shown by flow linear dichroism that trivaline beta-dimers preferentially binding with the single-stranded polymer rather than with the double-stranded one. It has been shown by electron microscopy that "the highest" compact structure of trivaline-poly(C) consists of dozens of "biduplex" structures. Beginning with a dimer trivaline-poly(U) complex, we proposed a schematic model for other complexes and compact structures of these molecules.

It was shown that trivaline-poly(U) complexes have no appreciable fluorescence at any peptide concentration if the polymer concentration is less than critical. By electron microscopy it was shown that dsDNA molecules undergo a second step of compactization if polymer and peptide concentrations are high enough. The diameter of this rod-like particles is over 40 nm. If the polymer concentration is less than critical, dsDNA molecules form with trivaline extended structures of dissimilar morphology. We propose a scheme of trivaline-dsDNA complexes and compact structure formation, beginning from a dimer complex. It is consistent with the results of equilibrium dialysis, fluorescence, electron microscopy, flow linear and circular dichroism measurements.

The protein-free method was applied for the investigation of histone H1 DNA complexes formation. The main advantage of this method is the possibility to get intramolecular compact structures at interaction of individual spread molecules of DNA with histone H1. It was shown that in the presence of 0.2-5 micrograms/ml of histone H1 in hypophase there are three types of structures on electronmicroscopic preparations: fibres of non-compacted DNA, compact fibres with twisted strands of duplex DNA and compacted rod-like and circular structures where separate fibres of duplex DNA could not be distinguished. The study of compact structures morphology allows to conclude that they are formed by side-by-side association of DNA fibres, as it takes place in the case of triple rings formation at the compactization of circular DNA due to trivaline binding. At increasing ionic strength there is a tendency for transition from second type structures to the third type structures. The latter can be explained by transition from non-cooperative to cooperative binding of histone H1 to DNA.

Binding of tripeptide H-Val3-(NH)2-Dns (TVP) to polyribonucleotides was studied by fluorescence methods, circular and flow linear dichroism, equilibrium dialysis and electron microscopy. It was found that TVP binds to poly(U) in monomer, dimer and tetramer forms with binding constants of about 10(3), 40, 18.10(4) M, respectively. The cooperativity parameter for peptide dimer binding is 2000. The peptide forms tetramer complexes with poly(A), poly(C), poly(G) also. The formation of a complex between the peptide tetramer and nucleic acid is accompanied by a significant increase in the fluorescence intensity. The cooperative binding of TVP dimers to poly(U), poly(A), poly(C) is accompanied by a dramatic decrease in the flexibility of polynucleotide chains. However, it has a small effect (if any) on the flexibility of the poly(G) chain. The observed similarity of thermodynamic, optical and hydrodynamic++ properties of TVP complexes with single-stranded and double-stranded nucleic acids may reflect a similarity in the geometries of peptide complexes with nucleic acids. Electron microscopy studies show that peptide binding to poly(U) and dsDNA leads to compactization of the nucleic acids caused by interaction between the peptide tetramers bound to a nucleic acid. At the first stage of the compactization process the well-organized rod-like particles are formed, each consisting of one or more single-stranded polynucleotide fibers. Increasing the peptide concentration stimulates a side-by-side association and folding of the rods with the formation of macromolecular "leech-like" structures with the thickness of 20-50 nm.

The cytoskeleton is considered to be a very important cellular component, playing a role in the interactions between different organelles. However, in many cases the true biochemical functions and some of the structural aspects of cytoskeletal filaments are still unknown. Several hybridoma cell lines producing monoclonal antibodies (Mab) against a complex of linear DNA with the tridecapeptide Dns-NH2-VVTGVKTGVKTVT-CO2H have been established. (Dns is 5-methylaminonaphthalene-1-sulphonic acid.) The organization of this complex, in which the DNA is in a compact form, has been well-characterized previously by physicochemical methods and electron microscopy. A monoclonal antibody, Mab 66/9, was selected for further study on the basis of its reactivity with the immunizing DNA-peptide complex and minimal reaction with DNA alone. In immunofluorescence studies with cultured cells, this Mab did not recognize any nuclear structures, but reacted with cytoskeletal intermediate filaments and with nuclear lamins. Thus, Mab 66/9 appears to define an epitope present in the immunizing DNA-peptide complex and in cytoskeletal elements. The epitope is probably determined by the conformation of the oligopeptide since it was not detected in denatured cell lysates. Our observations provide some indirect evidence in support of the DNA-binding properties of cytoskeletal components which have been hypothesized in some recent publications.

2-Aryl-4-methyl-4,5-epoxytetrahydropyrans, which react with piperidine regioselectively with trans-diaxial cleavage of the oxide ring at the least substituted carbon atom, were synthesized by the reaction of 2-aryl-4-methyl-3,6-dihydropyrans with peracids.

Binding of synthetic pentapeptide Val-Thr-Thr-Val-Val-N2H2Dns (where Dns is a residue of 5-dimethylamino naphthyl-1-sulfonic acid) is studied by circular dichroism, electron microscopy and fluorescence methods. It is found that this peptide can self-associate in aqueous solution as revealed from the concentration-dependent changes in the UV absorbance and fluorescence spectra. At high peptide concentration (3.10(-4) M) massive peptide aggregates are formed in solution and can be visualized by electron microscopy. It is shown that pentapeptide binds to DNA predominantly in a self-associated form and exhibits preferences for certain nucleotide sequences. It binds more strongly to poly(dG).poly(dC) and poly[d(A-C)].poly[d(G-T)] than to poly(dA).poly(dT). The complex with poly(dA).poly(dT) dissociates in the presence of 0.05 M NaCl, whereas the complex with poly(dG).poly(dC) is stable even in the presence of 0.2 M NaCl. The binding is a cooperative process which is accompanied by compaction of DNA at peptide/DNA base pair ratios greater than 2. At the initial stage of the compaction process the coalescence of DNA segments covered by bound peptide molecules results in the formation of DNA loops stabilized by interaction between bound peptide molecules. Increasing peptide/DNA ratio leads to the formation of rod-like particles as revealed from electron microscopy studies. Further increase in the peptide concentration leads to folding of fibrillar macromolecular complexes into globula each containing a single DNA molecule.

Compactization of supercoiled circular plasmid pBR322 caused by interaction with synthetic oligopeptide dansyl hydrazide trivaline capable of beta-structure formation was studied by electron microscopy. The results show that at rising input peptide concentration circular DNA molecules undergo intramolecular structural transition with the formation of compact ring structures. The compact ring structures are formed by the fiber having the thickness of 60 A. The analysis of morphology of intermediate structures and the contour length measurements enable us to conclude that 60 A-fiber contains three lying side-by-side and interwound double-stranded DNA segments. Thus, the compact ring structures are addressed to as triple rings. The triple ring have one special point, where the triple region ends are locked by a duplex DNA segment. The mechanisms responsible for the triple ring formation may be of importance for DNA and chromatin compactization processes in vivo.

The ELISA test using beta-lactamase for the detection of anti-AIDS virus antibodies and virus antigen in serum is described. The properties of this test system are compared with those of the system based on horseradish peroxidase conjugates.

The electron microscopic data on compactization of DNA at interaction with the synthetic oligopeptides having the trend of beta-structures formation in solutions are summarized. The new types of intramolecular and intermolecular compact structures are described in brief. Sequence of compactization process steps is discussed, the models of DNA packaging in the structures are presented. On the basis of the data presented the general principles of arrangement of the described compact structures are formulated, the mechanisms are proposed for formation of different types of compact particles on the final stage of the process of DNA condensation. Some processes of the genetic material compactization in vivo are discussed in which the proposed mechanisms for compact structures formation may have realization.

Studies on compactization and decompactization of the genome are of great importance for elucidation of structural mechanisms taking part in the regulation of gene activity. Kinetoplast DNA (kpDNA) is a convenient model for studies of compactization processes. KpDNA represents unique structure ("network"), consisting of catenated circular molecules of two types: minicircles (900 b.p.) and maxicircles (40 000 b.p.). The compactization process of kpDNA in vitro caused by interaction with synthetic peptide-dansylhydraside trivaline was studied. It was shown that at the initial stages the hairpins are observed on minicircles as if triple rings are being organized. The formation of hairpin is probably favoured by the presence in the minicircles of bent DNA, a specific nucleotide sequence causing rigid bending of the DNA helix. The hairpin does not make contact with the neighbouring DNA segment to form a triple ring, because the sizes of minicircles are too small. The minicircles compactization is finished with a complete collapse of the minicircles with the formation of rod-like structures. The catenation causes branching of rod-like structures. As a result of their intermolecular interaction, the branched rod-like structures become thicker. The process is completed with formation of the compact network, its diameter being 3-6 times smaller compared to the initial one.