Vol 54, No 4 (2018)

The success of plant adaptation in different agroecological conditions is largely determined by the heading time. In grain crops, this is one of the basic traits in description of the variety, since the selection of varieties by the appropriate heading time for the region of their cultivation provides maximal realization of the potential of the variety by the productivity. To develop wheat varieties adapted to certain conditions, it is important to understand the mechanisms of formation of this trait at a diploid and polyploid level of genome organization. This review summarizes the main mechanisms underlying the formation of the heading time of diploid and polyploid wheat forms; the genes whose change in the expression is associated with variation in the common wheat heading time are described. Besides the main mechanisms such as photoperiod sensitivity and vernalization requirement, the effects of the circadian rhythms genes, phytohormones, light receptors, microRNA, and some other factors that significantly contribute to the heading time formation are analyzed.

Polyploidy is the major mechanism of speciation in flowering plants. All genomes of ancient species that are the progenitors of extant plant species experienced polyploidization. Three consecutive stages of polyploidization, i.e., ancient polyploidization, tetra-, and hexaploidization, resulted in the emergence of modern allohexaploid bread wheat Triticum aestivum L. with the BBAADD genome. Polyploidization and subsequent stabilization of the polyploid genome of T. aestivum led, on one hand, to cytological diploidization and, on the other hand, to structural and functional asymmetry of its three subgenomes. In recent years, there has been a sharp increase in the data accumulation on the origin and structure of the bread wheat genomes a result of analysis of genomes and transcripomes of natural and synthetic wheats using modern mapping and sequencing methods. This review provides up-to-date information on the peculiarities of the T. aestivum genome reorganization, which affected its structure and functioning.

The present study aimed to develop a universal primer-multiplex PCR (UP-M-PCR) assay for the detection of six common bacteria associated with human meningitis. One optimal universal primer (UP) was selected from three UPs by comparing their sensitivities and specificities. All specific primers were tagged with the UP sequence at 5' end, and applied to the multiplex PCR system. The multiplex system was further optimized and assessed. This UP-M-PCR can successfully detect the six meningitis-associated pathogens with high specificity, and the sensitivity could reach up to 10 copies. In the identification of clinical specimens, six positive cases infected with Streptococcus agalactiae, Staphylococcus aureus, and Streptococcus pneumoniae were confirmed. The newly developed multiplex PCR system can be used to detect the six pathogens associated with human bacterial meningitis with high specificity and sensitivity.

The role of xyloglucan endotransglycosylases in the regulation and promotion of plant growth in response to such widespread stress factors as drought, salinization, and hypothermia remains poorly understood. The tXET-B2 (SlXTH10) gene encodes one of the xyloglucan endotransglycosylases of tomato, which is most closely related in the nucleotide sequence to the AtXTH15 and AtXTH16 genes of Arabidopsis thaliana. At present, the specific functions of the tXET-B2 gene, as well as of its homologs, AtXTH15 and AtXTH16, remain obscure. To study the role of tXET-B2 in the regulation of growth and adaptation to abiotic stress factors, transgenic tobacco plants with estradiol-inducible expression of the tomato tXET-B2 gene were generated. Overexpression of this gene promoted tobacco root growth in a medium containing 50 mM NaCl. Under drought conditions, exogenous treatment with estradiol resulted in a considerable increase in fresh and dry weight in many of the studied transgenic lines. Under normal conditions, as well as under salinization and hypothermia stress, such positive effect was detected only for some transgenic lines. The obtained data point to the possibility of using genetically engineered constructs of the tXET-B2 gene to correct growth parameters of transgenic plants under the influence of stress factors.

Adalia bipunctata Linnaeus, 1758 is a classical object for studying polymorphism of natural populations. Application of genetic markers significantly increased the possibilities of analysis of natural populations of ladybirds and opened the possibility of studying ecological adaptations at the genetic level. We analyze the geographical distribution of the mitochondrial haplotypes of A. bipunctata, determined on the basis of the variability of the mitochondrial cox1 gene in the natural populations of Norway. Two new mitochondrial haplotypes of A. bipunctata are described. We observe a geographical cline in the haplotypes frequencies from south to north. The main haplotype H1 of the central Europe is gradually replaced in the north by the haplotype H7. A possible reason for the observed geographical cline is a selective advantage of beetles with haplotype H7 in areas with a northern coastal climate.

A tremendous variety is observed in coat colouration of the Iranian indigenous sheep, whereas a few molecular based studies have been carried out to identify the responsible genes in this geographical area. Function and distribution of melanin, categorized as phaeomelanin and eumelanin determine the coat colour in vertebrates, which are primarily regulated by interactions of the two main loci, agouti and extension, currently termed as Agouti Signalling Protein and Melanocortin 1 Receptor, respectively. In current study, the upstream region and a part of the coding sequence of the MC1R gene were assessed in three Iranian sheep breeds, Zandi, Baluchi and Zel, through molecular methods and in silico predictions. PCR-SSCP results of the 5' UTR flanking region showed a clear banding pattern in which the E^ab was most frequent (67 per cent), observed in the individuals with light coloured phenotypes like white Baluchi and light grey and cream Zandi sheep, while the two homozygous patterns, E^aa and E^bb were rare in the populations. Direct sequencing the fragments revealed that the pattern is consistent with the–206G>A polymorphic site in the upstream region and four putative transcription binding sites close to this site were defined and characterized. The 12A>G and 51G>A transitions were also detected and verified as silent mutations in the 5' end of the coding region of the MC1R gene, with synonymous effect on amino acid sequence. Semi quantitative RT-PCR of various phenotypes resulted in acquisition of the highest expression in the dark grey phenotype of the Zel sheep.

Myocardial infarction (MI) is a multifactorial polygenic disease. It develops because of the complex interaction between many environmental and genetic factors. In this paper, we have studied associations of MI and allele combinations of 17 polymorphic markers of immune response genes in an ethnically homogeneous group of Tatars. The material for analysis was DNA samples of patients (286 men) with onset of MI at the age of 30 to 60 years and 301 essentially healthy men of the control group. Using the APSampler algorithm, we obtained allele combinations with the increased risk of MI in which allele variants CX3CR1*M (rs3732378), VCAM1*C (rs3917010), ICAM1*E (rs5498), LTA*A (rs909253), and TNFRSF1B*M (rs1061622) occurred the most often.

This work is devoted to personal identification of a pilot who perished during World War II in 1941. As a result of search works near the village of Sambek, participants of the search association Mius-Front found remains of a downed plane. We carried out complex genetic analysis of the mitochondrial and autosomal DNA isolated from the remains found among the plane fragments. For personal identification of the remains, recent relatives of crew members of the plane were found, who donated the biological material for comparative research. Owing to the analysis of DNA of the native niece of one of the pilots and the remains of the unknown person, it was possible to establish that these remains belong to Junior Sergeant Dzyuba Vladimir Romanovich, who was considered to be missing in action since October 17, 1941.

Robertsonian translocations (rob) are essential in the etiology of congenital malformations and reproductive disorders. However, to date, there has been no systematic comparative analysis of both the frequency and spectrum of rob in different carrier populations. Also, due attention was not paid to the phenomenon of the exceptional rarity of some types of rob. In this paper, the spectrum of rob was determined in the reference group (newborn carriers from the general population and carriers diagnosed prenatally for indications other than family rearrangement) in comparison with groups of carriers with reproductive disorders (infertility and pregnancy loss). The overall rates of rob in the studied groups were calculated as 1.05, 3.3, and 5‰, respectively. It was suggested that homologous translocations do not cause disturbances in spermatogenesis. A rarity of some certain types of translocation could be explained by selection.