Basic chromosome numbers are compared among species of four gymnosperm divisions, three Anthophyta families, and three Mammalia subclasses, with different life cycle types. Gymnosperm and angiosperm species characterized by alternation of haploid and diploid phases, sporic meiotic reduction, hermaphroditism, and sporophyte predominance have small basic chromosome numbers (BCNs): x = 7 to 14, and most of their species are polyploids. Species of various mammal subclasses, with sporophyte predominance gametic meiotic reduction, dioecious, and characterized by a chromosomal sex-determination system broadly vary in BCN. Monotremata species (oviparous) have small BCNs and ploidy levels 10x. The BCN variability among marsupials is x = 5 to 16, and in Euarchontoglires (placentals) x = 3 to 51. No polyploids have been found among marsupials or placentals.

Data on chromosome banding and various kinds of fluorescence hybridization of chromosome-specific probes indicate that the BCN evolution in angiosperms was accompanied by repeated crosses and polyploidization of species with few chromosomes followed by dysploidization by means of conjugation of nonhomologous chromosomes and reciprocal translocations. It is believed that the BCN of the placental ancestor was x = 40–50; of the marsupial ancestor, 16–20; and of oviparous mammals, 5–6. The significant difference among BCNs of the ancestors of the three mammal subclasses, which diverged tens of millions of years ago, suggests that the evolution of BCNS in the ancestors of marsupials and placentals involved polyploidy followed by dysploidy.

The species analyzed demonstrate a correlation between life cycle type and BCN.

The results indicate that the genetic difference in sex determination systems were the main cause of BCN variation in the species analyzed, differing in life cycle type. The lengths of the haploid and diploid phases are of minor significance.

The notion of meiosis has been changed and refined for over a century since the discovery of this complicated way of cell division. Its success depends on precise time and space orchestration of many processes, such as chromosome replication, packaging, exchange of homologous regions, alignment in the plane of division, and disjunction. The development of molecular and immunocytochemical methods in recent decades cast light on the details of these processes and brought scientists closer to the understanding of mechanisms regulating them. This review presents the current notion of the major meiotic events by examples of yeast and mammals. Particular attention is paid to processes underlying chromosome synapsis and recombination, as well as monoorientation of sister kinetochores in the first division, the key features distinguishing meiosis from mitosis and ensuring chromosome number reduction.

Factors determining the phenotype formation in patients with abnormal karyotype (including those with Down’s syndrome) have been discussed for several decades. Earlier, we considered factors affecting phenotype formation in patients with chromosomal aberrations (Grinberg, 1978, 1982; Grinberg, Kukharenko, 1992). We believe that the general concept of the phenotypic manifestation of chromosomal disbalance must take into account the following factors:

1. The alteration in the number of chromosomes, in addition to specific effects connected with the dose of the genes located in a particular chromosome is accompanied by a nonspecific effect, which is manifested in the oppression of growth and development of the organism.

2. Birth defects observed in persons with chromosomal aberrations are persisting conditions, which are normal at earlier developmental stages. The main effects of chromosomal aberrations are hypomorphic. Nevertheless, these birth defects actually do not differ from developmental defects caused by particular genes and teratogenic environmental factors.

3. The phenotypic manifestation of chromosomal imbalance may be based on disturbances of the basic and elementary events in morphogenesis, occurring at the cell level. Such events are proliferation and migration of cells, specific reception, and induction relationships.

4. It is supposed that changes of metabolic homeostasis in cells with abnormal karyotypes favor the manifestation of the latent variability of structures that support the basic morphogenetic functions in cells. It is conceivable that chromosomal aberrations strengthen the evolutionarily conditioned variability towards the delay of maturation of cellular and tissue structures, which is the key link in the pathogenesis associated with chromosomal imbalance.

Androgenesis has been studied in anther cultures of eight cultivars and one promising accession of spring common wheat raised in West Siberia (Siberian Research Institute of Agriculture, Omsk, Russia). The varieties are close in origin but vary in the presence or absence of wheat-alien translocations (wheat–rye 1RS.1BL and wheat–couch grass 7DL-7Ai). The promising accession L-311/00-22 bears the 1RS.1BL translocation and the cytoplasm of cultivated barley Hordeum vulgare L. The main task of the study is to assess the possibility of obtaining dihaploid lines in the genotypes examined bearing wheat-alien translocations. It has been found that different accessions respond differently to anther culture conditions depending on the concentration of 2,4-D in the initial medium. Accession L-311/00-22 is best for androgenesis experiments and raise of dihaploid lines. The dependence of the effect of the genotypic environment of wheat on the effect of wheat-alien translocation on androgenesis features, is discussed.

Allelic combinations of the Vrn-H1, Vrn-H2, Vrn-H3, Ppd-H1, and Ppd-H2 genes have been investigated with allele-specific molecular markers in 91 spring barley cultivars recommended for use in Russia and Belarus. In a field experiment under conditions of North-West Russia, heading date evaluation has been performed in these cultivars.

Barley varieties having the dominant Ppd-H1 allele were shown to overrun other genotypes in the developmental rate (heading date) and to mature earlier under long-day conditions. Among studied cultivars, grown in Russia, only 9 % possessed the dominant Ppd-H1 allele. A significant association was also found between the allele combination of Vrn genes and heading date of barley cultivars. Among cultivars with identical genotypes for Ppd-H1 and Ppd-H2, those having the allelic combination Vrn-H1vrn-H2Vrn-H3 flower significantly earlier than with other haplotypes. The use of allele-specific markers of Ppd and Vrn genes makes breeding for early ripeness easier and faster.

RAPD analysis of sweet pepper lines of various ecogeographical origins was made to study DNA screening efficiency for hybrid breeding. Genetic distances among parental lines were calculated. The collection was classified by UPGMA. Hybridization of polymorphic genotypes was carried out in 5 × 5 diallel cross. The combining ability of lines and the F1 heterosis effect were evaluated. Combinations with high levels of heterosis for performance traits were revealed. The contributions of additive and dominant genes to the realization of the genetic potential of parental lines were determined. Our study showed that the specific combining ability of lines of the sweet pepper collection was more important for the formation of heterosis than the general combining ability. Positive correlations between DNA marker distances of parents and heterosis degree were found for some performance traits, however, their levels were low. We plan seeking specific DNA loci that would be positively associated with hybrid performance.

The variability of chloroplast number and plastotype number in stomata guard cell populations was analyzed. Experiments were done with three types of plants: inbreed lines, a synthetic population and commercial heterosis hybrids. Chloroplast numbers in stomata guard cells of different plant groups are different: the greatest chloroplast number was recorded in inbred lines and triploid hybrid, and the smallest, in commercial  hybrids. The greatest number of plastotypes was observed in inbreed lines, and the smallest, in hybrids. The fractal dimension of stomata guard cell populations was used for characterization of tissue cells in sugar beet. It estimates in a logarithmic scale the ratio between the chloroplast number and plastotype number. In the samples studied, it varied from 1,17 to 1,23 in inbred lines and from 1,23 to 1,35 in commercial hybrids (average 1,272).

Hybrid plants were obtained by pollination of Nicotiana rustica and Nicotiana tabacum Black Cuban cultivar with pollen of transgenic Nicotiana tabacum plants of Petit Havana SR1 cultivar bearing the ARGOS-LIKE and AtEXPA10 genes. RT-PCR analysis showed high levels of ARGOS-LIKE and AtEXPA10 expression in the hybrids. It led to an increase in the sizes of their leaves and stems. Organs of both transgenic and hybrid plants were enlarged due to the enlargement of individual cells. The inheritance was stable, but the phenotypic effects varied from insignificant to levels exceeding those in parental transgenic plants.

The mechanisms of aluminum resistance, acting at the cellular level, provide an opportunity of obtaining resistant forms of plants by the cell culture method. In practice, however, this approach has not become widely used because of difficulties of plant regeneration from callus culture. This article focuses the attention of readers on other causes of low efficiency of the approach. They include high intraspecific heterogeneity of cereal crops with regard to aluminum resistance; conventionality of the division of genotypes into resistant and sensitive, accepted in practice; appearance of acid- and aluminum-resistant regenerants not only under stress but also under control conditions without any action of the stress factor under study; lack of appropriate methods, connected to the specific behavior of aluminum in various media, when incorrectly chosen medium composition or рН conceal the action of aluminum. As a result of joint action of all reasons mentioned in the article, the offered techniques of creation of high-resistant regenerants of cereal crops are behind traditional methods of intravarietal selection in duration, labor consumption, cost, and efficiency.

Small non-coding RNAs are a specific class of RNAs that regulate a variety of physiological processes in plants. Small RNAs (siRNAs and miRNAs), the pathways of formation and, particularly, their putative functions in plant defense against biotic and abiotic stresses are concisely reviewed. Techniques that enable use of this class of RNA as agents for managing plant resistance are discussed.

The regulatory region of the Escherichia coli yfiA gene was reconstructed by using the SiteCon web resource and mathematical modeling, and its expression complexity under oxidative stress was assessed. Simulation of the response of E. coli cells transformed with pYfi-gfp plasmid to oxidative stress indicated that the maximum agreement with experimental data was achieved in a model implying a complex action, apparently mediated by several transcription factors (TFs). The regulatory region of the yfiA gene was searched for potential TF binding sites, and highly reliable recognition was predicted for TFs MarA, IscR, MetJ, PurR, and SoxS, which directly or indirectly participate in the response of the gene to oxidative stress, and for CRP, a global regulator of carbohydrate catabolism. The presence of binding sites for CRP, MarA, and SoxS in the E. coli yfiA promoter was confirmed by electrophoretic mobility shift assay with purified recombinant TFs. This fact explains the sensitivity of yfiA to mitomycin and radical-forming agents.

Sequence variation in the 538-bp fragment from the 5′ end of the COI region was analyzed to test its usefulness in the identification of 15 mosquito species of the genera Aedes and Ochlerotatus (Diptera: Culicidae) from Tomsk and Kemerovo regions and 14 species from GenBank. The divergences between congeneric species averaged 7,8 % (from 0,7 to 13,1 %), whereas those for conspecific individuals averaged 0,57 % (0 to 1,6 %). The sequences for four species pairs (3,7 %) showed < 2 % divergence. In most cases, individuals of a single species grouped closely together, but deeper divergences were detected in two species (Och. euedes and Ae. vexans).

We have shown that among 13 inbred mice strains males the DD/He strain has the lowest proportion of mobile sperm and moderate sperm count and proportion of abnormal sperm heads. Males of the BALB/cLac strain have the highest proportion of mobile sperm and abnormal sperm heads, but a moderate sperm count. It is known that Y chromosome genes are important for spermatogenesis. Thus, Y chromosome mutations may be responsible for interstrain differences in spermatogenic parameters. Reciprocal cross can be a useful tool to examine the effect of the Y chromosome on sperm count and the proportions of mobile and morphologically abnormal sperm. The sperm count in DD/He males is higher than in BALB/cLac ones, but both crosses show equal values, exceeding those in the paternal strains. Males of cross BALB/cLac × DD/He have a higher proportion of mobile sperm than males of DD/He × BALB/cLac. The greatest proportion of abnormal sperm heads has been recorded in the BALB/cLac strain. The proportions of abnormal sperm heads in the hybrids were small but little different from each other.

The synergic action of the cytostatic drug cyclophosphamide (CP) and fragmented exogenous DNA causes illness and death in mice (Dolgova et al., 2011–2013). The observed «delayed death» effect was most clearly pronounced when the DNA preparation was administered 18 to 30 hours after CP treatment. This time span is designated as «death window».

It was found that injections of exogenous DNA result in sustained increase in bone marrow cell (BMC) apoptosis, which occurs throughout the time of DNA administration (18–30 hours). Exogenous DNA, both allogeneic and belonging to various taxa induces BMCs apoptosis. Plasmid DNA has the greatest effect on apoptosis induction.

The analysis of reduction and restoration of BMC subpopulations as the mice progressed to death revealed a virtually complete loss of the 12–20-mkm fraction of the cell population (about 3–4 % vs. 35–40 % in the control), which corresponds to the maximum leukopenia on day 3 after CP treatment. However, the relative amount of CD34+ hematopoietic stem cells (HSCs) from day 15 and till the end of the observation constituted 1,2–1,4 %, which corresponds to the wild-type range. Comparison of BMC smears from the sternal bone marrow of the CP and CP+DNA groups of mice indicates that the BMC populations isolated from CP+DNA animals lack young committed lymphopoiesis progenitor cells. Moreover, the affected mice had immature blast cell types in their blood, which was never observed in healthy or CP-treated mice. Pathological and morphological analyses show that starting from posttreatment day 9, mice that received CP+DNA preparations displayed pronounced morphological changes in their lungs, liver, pancreas, central and peripheral immune system organs, and brain. Most of the pathological changes observed are consistent with severe inflammatory response. This suggestion is proven by structural equivalents of functional involution of lymphoid organs, such as thymus, spleen, and lymph nodes.

We speculate that the death of treated animals resulted from multiple organ dysfunctions caused by accidental involution of lymphoid organs and the systemic inflammatory response syndrome, both associated with injections of fragmented exogenous DNA into experimental animals within the «death window», which corresponds to the final step in the repair of the majority of CP-induced double-strand breaks.

Rederivation allows laboratory animal populations to be purged from specified pathogens and thus turns these animals to the SPF (specified pathogens free) status. Results of the rederivation of two unique rat strains selected at the Institute of Cytology and Genetics and one mouse strain are presented. The two rat strains are: tame Norway rats and rats with Inherited Stress Induced Arterial Hypertension (ISIAH strain). The ICR mouse strain has been named as abbreviation of the Institute of Cancer Research wherefrom these mice were distributed to laboratories all over the world. The SPF status of the rats after rederivation was confirmed by the method of indicator animals (sentinel animals). The optimized model of rederivation offered here involves a combination of such embryotechnological methods as freezing/cryopreservation of embryos, their washing through the number of fresh volumes of sterile media, growing in vitro for 48 hours, and subsequent transfer into either one or both uterine horns of recipient females. Application of this model to rederivation of ICR mice yielded 39 pups born in an SPF vivarium. It should be noticed that the effectiveness of the procedure met international standards, and characteristic features of phenotype were retained in all the three strains after rederivation.

Within one year since May 1930 till August 1931 Th. Dobzhansky undertook an intership in the USA on a scholarship from the International Education Board (The Rockefeller Foundation). His preparation for returning to the USSR included all necessary actions for getting a new job and prolongation of his and his wife’s passports. After receiving three letters from N.I. Vavilov, of June, 9, 11 and 12, 1931, Th. Dobzhansky decided to stay in the USA and became an asylee (the Russian term “nevozvrashchenets” literally means non-returner). In 1932, at the 6th International Genetic Congress in Ithaca, USA, N.I. Vavilov said that Dobzhansky’s decision was sound.

The paper concisely reviews the history of establishment of the idea on evolutionary synthesis involving plant objects and its experimental justification. The roles of S. Navashin, E. Babcock, and G.L. Stebbins in the construction of experimental background for evolutionary synthesis involving botanical material are described. The history of the development of Stebbins’ views of the role of hybridization and polyploidy in plant evolution is considered, as well as his brilliant insight into the role of whole genome duplication in the expansion of variation, which were proven only after the advent of the genomics approach.