Scientific Bases for Enuring Productive Longevity of Agrolandscapes in Russia

Biology Bulletin - V.V. Dokuchaev’s ideas are the foundation of modern ideas about rational nature-usage methods in our steppes in order to ensure productive longevity of agro-ecosystems and...     

Segment duplications in the human genome

The review considers the structure, evolution, and possible mechanisms of spreading of intrachromosomal and interchromosomal segment duplications (SD), which account for more than 5% of the human genome. Most SD are mosaic and consist of multiple modules, which occur in several copies in different genome regions. SD are preferentially located in pericentric and subtelomeric regions, which are least studied on the human chromosomes. Homologous recombination between SD results in various chromosome rearrangements, contributing to the genome instability and the origin of several human hereditary disorders.     

Effect of pineal peptide on parameters of the biological age and life span in mice

Female CBA mice were injected with s.c. synthetic tetrapeptide Epithalon from a 6-month age until death. The drug failed to affect the body weight or food consumption, physical activity or behavioural parameters. However, it slowed down the age-related switching off of the estrus function, decreased body temperature, decelerated free redical processes, prolonged the mice life span with an accompanying drop in spontaneous tumour incidence.     

Identification of proteins with altered expression in colorectal cancer by means of 2D-proteomics

Modern proteomic techniques make it possible to identify numerous changes in protein expression in tumors as compared to normal tissues. Although proteomics is currently widely used, identification of proteins differentially expressed in particular types of cancer remains a challenging task. The goal of our study was to detect novel protein markers of colorectal cancer using comparative proteomics of protein extracts obtained from primary tumors and adjacent normal tissues. Coloreetal cancer is nearly asymptomatic at the early stages, which calls for development of fast and sensitive methods for molecular diagnostics. Proteomes of 11 paired specimens of primary colorectal tumors and adjacent histologically normal tissues were studied using comparative 2D PAGE. Altogether, 16 proteins with altered expression levels were detected, including 13 proteins with increased levels and three proteins with decreased levels in tumor tissues. These proteins were identified using MALDI-TOF mass spectrometry. The proteins GPD1, RRBP1 (increased levels), HNRNPH1, and SERPINB6 (decreased levels) have been associated with colorectal cancer for the first time.     

Statistical Analysis of the Influence of a Disturbance Factor on Formation of the Spatial Structure of the Great Bustard (<Emphasis Type="Italic">Otis tarda</Emphasis> L.) (Otididae,Aves) Population in the Trans-Volga Region

This paper examines the influence of the location of settlements, railroads, and highways on the spatial structure of the Otis tarda population in the Trans-Volga region that was studied in the years 1998–2016 in a model area of 12000 km² that is located in the southern part of the Saratov Trans-Volga region. The zone of the impact made by our estimated disturbance factor due to the movement of people and a variety of ground vehicles along various-purpose roads on the territorial distribution of bustards in autumn can be denoted as a 300–500 m width band on both sides of the transport communications. Shelterbelts that were created along transport communications render a beneficial effect on the distribution of O. tarda and reduce the influence of the disturbance factor. Furthermore, crop rotation fields with side sizes of more than 1 km can be considered a factor that compensates for the anxiety of birds. We have found that in the Saratov Trans-Volga region, because of the large size of crop rotation fields and significant development of roadside and shelter belts, no special measures are required to protect O. tarda such as restrictions on the movement of people and vehicles over the territory where this species lives.     

Use of an aerodynamic foam quencher in the stab cultivation of mycelial fungi

A scheme for automatic impulse foam breaking during biosynthesis of cephalosporin C in 0.63 m3 pilot plant fermenters was developed and tested. It was shown that the use of an aerodynamic foam breaker did not limit the antibiotic biosynthesis by oxygen and promoted stabilization of the foam level in the apparatus without chemical antifoamers and increased air supply.     

Impact of recombination on polymorphism of genes encoding Kunitz-type protease inhibitors in the genus Solanum

Background

The group of Kunitz-type protease inhibitors (KPI) from potato is encoded by a polymorphic family of multiple allelic and non-allelic genes. The previous explanations of the KPI variability were based on the hypothesis of random mutagenesis as a key factor of KPI polymorphism.

Results

KPI-A genes from the genomes of Solanum tuberosum cv. Istrinskii and the wild species Solanum palustre were amplified by PCR with subsequent cloning in plasmids. True KPI sequences were derived from comparison of the cloned copies. “Hot spots” of recombination in KPI genes were independently identified by DnaSP 4.0 and TOPALi v2.5 software.The KPI-A sequence from potato cv. Istrinskii was found to be 100% identical to the gene from Solanum nigrum. This fact illustrates a high degree of similarity of KPI genes in the genus Solanum. Pairwise comparison of KPI A and B genes unambiguously showed a non-uniform extent of polymorphism at different nt positions. Moreover, the occurrence of substitutions was not random along the strand. Taken together, these facts contradict the traditional hypothesis of random mutagenesis as a principal source of KPI gene polymorphism. The experimentally found mosaic structure of KPI genes in both plants studied is consistent with the hypothesis suggesting recombination of ancestral genes. The same mechanism was proposed earlier for other resistance-conferring genes in the nightshade family (Solanaceae).Based on the data obtained, we searched for potential motifs of site-specific binding with plant DNA recombinases.During this work, we analyzed the sequencing data reported by the Potato Genome Sequencing Consortium (PGSC), 2011 and found considerable inconsistence of their data concerning the number, location, and orientation of KPI genes of groups A and B.

Conclusions

The key role of recombination rather than random point mutagenesis in KPI polymorphism was demonstrated for the first time.     

Genetic diversity and evolution of the influenza C virus

The influenza C virus is spread worldwide and causes diseases of the upper and (less frequently) lower respiratory tract in human. The virus is not pandemic, but it circulates together with pandemic influenza A and B viruses during winter months and has quite similar clinical manifestations. The influenza C virus is also encountered in animals (pigs and dogs) and is known to override the interspecific barriers of transmssion. The immune system of mammals often fails to recognize new antigenic variants of influenza C virus, which invariably arise in nature, resulting in outbreaks of diseases, although the structure of antigens in influenza C virus in general is much more stable than those of influenza viruses A and B. Variability of genetic information in natural isolates of viruses is determined by mutations, reassortment, and recombination. However, recombination events very rarely occur in genomes of negative-strand RNA viruses, including those of influenza, and virtually have no effect on their evolution. Unambiguous explanations for this phenomenon have thus far not been proposed. There is no proof of recombination processes in the influenza C virus genome. On the contrary, reassortant viruses derived from different strains of influenza C virus frequently appear in vitro and are likely to be common in nature. The genome of influenza C virus comprises seven segments. Based on the comparison of sequences in one of its genes (HEF), six genetic or antigenic lineages of this virus can be distinguished (Yamagata/26/81, Aichi/1/81, Mississippi/80, Taylor/1233/47, Sao Paulo/378/82, and Kanagawa/1/76). However, the available genetic data show that all the seven segments of the influenza C virus genome evolve independently.