Differentiation of strains of bovine infectious rhinotracheitis virus using restriction analysis]

The virus of infectious rhinotracheitis of cattle (BHV-1) causes the respiratory diseases, encephalitis, vulvovaginitis, abortions, etc. in sensitive animals. The attempts to differentiate the viral strains by virology and serology methods were unsuccessful. The restriction analysis makes possible to divide the strains into the three main groups designated BHV-1.1, BHV-1.2 and BHV-1.3. Majority of authors note the lack of correlation between the restriction pattern of DNA and the syndromes caused by the strains of the first and second groups while all the representatives of the third group were isolated in case of meningoencephalitis. The restriction analysis of BHV-1 strains isolated in the USSR by restriction endonucleases EcoRI, BamHI, HpaI and ClaI is presented. The obtained results show the absence of correlation between the restriction pattern of the strain and the syndrome caused by the viruses of all three groups. The representatives of the group BHV-1.3 that are not associated with the neurological syndrome are isolated for the first time.     

Chemical-enzymatic synthesis and cloning of the full-length genome of a DNA-containing plant virus]

The full-length genomic DNA of a small plant virus--coconut foliar decay virus (CFDV)--has been synthesized by a combination of chemical synthesis, ligation and polymerase chain reaction. Three separately cloned DNA fragments of the genomic DNA were sequenced and assembled in the pPCV002 plasmid vector.     

Structures of the Mouse Central Nervous System Contain Different Quantities of Proteasome Gene Transcripts

Molecular Biology - Proteasomes are multisubunit complexes that degrade most intracellular proteins. Three of the 14 subunits of the 20S proteasome, specifically β1, β2, and...     

Availability and canonical positioning of key amino acids of ornithine-decarboxylase degron is insufficient for alpha-fetoprotein degradation

Ornithine decarboxylase (ODC) degrades in proteasome in a ubiquitin-independent manner with the half life of approximately 2 h. Thirty seven C-terminal amino acids of this enzyme constitute a fragment known as the degradation signal (degron), which is responsible for the effectiveness of protein degradation. Among these amino acids, the key positions have recently been mapped (Cys441 and Ala442). Mutations of the key amino acids led to ODC general stabilization, whereas substitution of other amino acids had no significant influence on the ODC degron activity. In addition, deletions or insertions into the region located between the key amino acids and ODC C-end diminished significantly the rate of protein degradation; hence, the distance (remoteness) of these amino acids from ODC C-end is, probably, of crucial importance. Taking into account these data, we have introduced the key amino acids that determine ODC-degron activity into alpha-fetoprotein with the truncated export signal (ΔAFP) so that their positioning was 20 amino-acid away from the C-end (ΔAFPCAG and ΔAFPLCAG). Secretion of ΔAFP and the modified proteins from cells was impossible because of a removal of the N-terminal export signal. Computer analysis of ΔAFP and the derivative ΔAFPCAG and ΔAFPLCAG revealed no significant changes in protein hydrophobicity or in the secondary structure of C-terminal region. The in vitro experiments on HEK293T cells using MG132 proteasome inhibitor and translation inhibitor cycloheximide have demonstrated similar stability of ΔAFP and the derivative ΔAFPCAG and ΔAFPLCAG in cells. Thus, introduction of the key amino acids of ODC degron at the key positions relative to the C-end of ΔAFP did not change the parameters of protein degradation. Perhaps, some other still unknown amino acids are important for ODC-degron functioning. It may well be that ΔAFP conformation prevents interaction of the protein C-end with proteasome.     

Fauna of Sipunculans (Sipuncula) of Vostok Bay, Sea of Japan

Fauna and systematics of sipunculans inhabiting Vostok Bay, Sea of Japan, are discussed. A revision of the local species of sipunculans is performed for the first time. On the basis of study of outer and inner morphology, some species are reduced to synonyms. Extended diagnoses are proposed for all registered species. An identification key is presented for the sipunculans of Vostok Bay.     

Peculiarities of the growth and morphology of human fibroblasts cultured on substrates modified with nanosized fibers of collagen and chitosan

The relationship between cell morphology and the topography and composition of a substratecoating material based on nanosized fibers of collagen and chitosan was studied during culturing the cell culture of normal human embryonic fibroblasts. The morphology of cells grown on modified substrates (in particular, the number of cilia and flagella up to 100 nm in diameter) was studied by atomic force microscopy at the submicron level in comparison with their proliferative activity on glass substrates. Methods for controlling the growth activity by changing the structure and composition of the coating material were proposed. The effect of the reduced pH of the coating material surface on growth activity and cell morphology was studied. Methods of spray application of colloidal solutions of biopolymers were proposed.     

Mechanical denaturation of lysozyme in a crystal and film

A method for taking stress-strain diagrams in microsamples prepared from glutaraldehyde-treated monocrystals and amorphous films of hen egg-white lysozyme has been developed. Analysis of the diagrams has shown that the deformation obeys Hooke's law within 0-2%. Upon further deformation of a crystalline sample (up to 6-10%) when a critical tension, sigma cr, is reached, the protein molecules in the sample denature and become greatly extended. Depending on crystal type and crystallographic direction the sample length increases 2 to 4 times. The sample deformation accompanying denaturation is reversible: when the sample is kept at high temperature it restores completely its initial length. The critical stress is essentially dependent on temperature, hydration level, urea concentration, the factors affecting intra- and intermolecular interactions.     

Role of peripheral adrenoreactive structures in the etiology of disorders of the motor components of rat operant behavior during emotional stress

It has been found in experiments on rats trained to avoid electric stimulation of the foots by pressing the pedal that previous immobilization and administration of adrenaline and isoprenaline (but not noradrenaline) disturbs the accuracy of the realization of motor components of operant behavior. The total beta-adrenoblockers (but not phentolamine and cardioselective beta 1-adrenoblockers) given in doses which do not cause any central effects reduced the negative action of emotional stress. It is inferred that activation of beta 2-adrenoreceptors of skeletal muscles is likely to play a role in the genesis of disturbed motor skill under emotional stress.