THE development of cytology in its relation to genetics is a chapter of more than usual interest in the history of biology. Cytology in the modern sense developed during the last quarter of the nineteenth century as a purely observational science. The general nature and behaviour of cells, nuclei and chromosomes were worked out during that period, although the cell theory, of course, originated much earlier. The rediscovery of Mendelism and the announcement of mutation at the turn of the present century marked a new epoch in biology, and soon gave abundant meaning to the observations regarding chromosomes which the cytologists had already accumulated. Henceforth cytology and the young science of genetics mutually influenced each other, and each derived increasing strength from the observations of the other. Introduction to Cytology. By Lester W. Sharp. (McGraw-Hill Publications in the Agricultural and Botanical Sciences.) Third edition. Pp. xiv ‘ 567. (New York and London: McGraw-Hill Book Co., Inc., 1934.) 30s. net.

Cytology and Genetics

https://www.ibb.waw.pl/~plantpath/pdf/Anexines_Plant%20Science_2011.pdf

Structure, function and membrane interactions of plant annexins: an update.

Genes conferring resistance to antibiotics have been widely used as markers for the selection of transformed cells in the development of genetically modified (GM) plants. Their presence in GM plants released in the environment or used as food or feed has raised concerns over the past years regarding possible risks for human health and the environment. Although these concerns have not been supported so far by scientific evidence, the implementation of selection approaches avoiding the presence of antibiotic resistance marker genes (ARMGs) in the final GM plant is increasingly considered by GM plant developers, not only to alleviate the above-mentioned concerns, but also to circumvent technical limitations associated with the use of ARMGs. In the current paper, we present the results of a three-step analysis of selectable markers and reporter genes as well as methods aiming at developing marker-free GM plants. First, based on a comprehensive review of the scientific literature, technical developments in this domain are presented. Second, a state-of-the-art of the current use of selection approaches is provided based on publicly available information on GM plants tested in the field or authorized for commercialization. Third, in order to get more insight in the underlying practical, scientific and/or regulatory arguments supporting the choice of selection approaches, we present the results of a survey directed at relevant developers and users of GM plants. The applicability, efficiency, operational access and biosafety of the various selection approaches is discussed and considered in light of their current use, and in perspective to the long history of use of ARMGs in plant biotechnology.

https://www.tandfonline.com/doi/pdf/10.1080/07352689.2013.870422

Alternatives to antibiotic resistance marker genes for in vitro selection of genetically modified plants: scientific developments, current use, operational access and biosafety considerations

Development of transformation vectors based upon a modified plant α-tubulin gene as the selectable marker

Jatropha gossypiifolia L. (Euphorbiaceae) is widely used in popular medicine. However, further toxicological studies are necessary for its reliable use. The present study aimed to evaluate the cytotoxic, genotoxic, and mutagenic effects of ethanolic and aqueous leaf extracts of J. gossypiifolia, using the test system Allium cepa. In addition, the phytochemical profile of the extracts was also obtained. Seeds of A. cepa were subjected to different concentrations of the two extracts (0.001, 0.01, 0.1, 1, and 10 mg/mL). Distilled water was used for the negative control and methyl methanesulfonate (4 x 10(-4) M) and trifluralin (0.84 ppm) for the positive controls. The values of mitotic index at all concentrations of ethanolic extract and at 0.1, 1, and 10 mg/mL aqueous extract showed a significant decrease. Alterations, such as chromosome adherence, C-metaphases, chromosome bridges, nuclear buds, and micronuclei were verified in both extracts but chromosome loss indicating genotoxic activity was observed only in the ethanolic extract. Presence of micronuclei on administration of the extracts, also indicated mutagenic action at the chromosome level. In the ethanolic extract, aneugenicity seemed to be the main activity, probably as a result of the action of terpenes and/or flavonoids, whereas in the aqueous extract, clastogenic action appeared to be the principal activity, presumably as a consequence of the effect of flavonoids and/or saponins. Thus, we suggest that the extracts of this species should be used with great caution for medicinal purpose.

/pdf/genotoxic-potential-of-leaf-extracts-of-jatropha-3jzcvzh22i.pdf

Genotoxic potential of leaf extracts of Jatropha gossypiifolia L.

Eleven plant homologuess of animal and yeast STE20-like protein kinases were identified. It was shown that unknown proteins A9RVK0 of the moss Physcomitrella patens ssp. patens and A7P2E2 of the grape Vitis vinifera were the closest plant homologues of STE20-like protein kinases. The Ste20-like protein kinase dst1 of the myxomycete Dictyostelium discoideum was the closest to the plant homologues. The spatial structure of the catalytic domain of the protein A9RVK0 from P. patens ssp. patens was predicted.

Bioinformatics Search for Plant Homologues of Ste20-like Serine/Threonine Protein Kinases

Method of biolistic transformation was used for genetic improvement of commercial barley cultivars (Oksamitoviy, Vodogray and Getman). The plasmid pHLFTuBA was used for particle bombardment that consists of the hLF gene under the control of the barley glutelin B-1 promoter and a selectable marker gene, alpha-tubulin conferring resistance to trifluralin (dinitroanilinr herbicide). Preliminary screening of different trifluralin concentration range from 0,1 to 30 microM was tested for determination of effective selective agent concentration. Two transgenic barley line of genotype Oksamitiviy and transgenic callus line of cultivar Getman were obtained after selection on 10 microM of trifluralin. To confirm the transgenic nature of regenerated plants, the PCR analysis was carried out. The 734bp length fragment of hLFgene was amplified from both regenerated plants.

[Developing transgenic barley lines producing human lactoferrin using mutant alfa-tubulin gene as selective marker gene].

In order to investigate the role of various serine/threonine protein kinases and protein phosphatases in the regulation of mitosis progression in plant cells, the influence of cyclin(olomoucine) and Ca2+/calmodulin-dependent (W7) protein kinases inhibitors, as well as protein kinase C inhibitors (H7 and staurosporine), and a protein phosphatases inhibitor (okadaic acid) on mitosis progression in synchronized tobacco BY-2 cells has been studied. It was found that BY-2 culture treatment with inhibitors of cyclin-dependent protein kinases and protein kinase C caused a prophase delay, reduced the mitotic index, and displaced the mitotic peak as compared with control cells. Inhibition of Ca2+/calmodulin-dependent protein kinases enhanced the cells entry into prophase and delayed their exit from mitosis. Meanwhile inhibition of serine/threonine protein phosphatases insignificantly enhances synchronized BY-2 cells entering into all phases of mitosis.

Effect of serine/threonine protein kinases and protein phosphatases inhibitors on mitosis progression in a synchronized tobacco BY-2 culture

N. sylvestris mutants resistant to isopropyl N-phenyl carbamate (IPC), a herbicide belonging to the phenyl carbamate series, are obtained by means of in vitro selection using gamma radiation. A concentration of 30 μM IPC was found to be the maximum concentration at which mutants of the N. sylvestris line capable of regeneration and rooting under conditions of selection pressure could be selected. IPC resistance in the mutants obtained was confirmed by a number of tests, in particular, tests that measure the capacity of leaf explants of the mutant lines to regenerate plants and the ability of their callus cells to survive in media with a selective IPC concentration, as well as by means of genetic, morphometric, cytological, and immunofluorescent analyses. The results of these studies attest to increased resistance of the mutant plants to this antimitotic substance by comparison with a control. It is shown that resistance to IPC is based on the heightened resistance of the microtubule organizing centers of the cells of these lines. It is established that the acquired resistance trait inherited in the F1 and F2 generations of the mutants is a dominant nuclear trait.

Nicotiana sylvestris L. mutants resistant to isopropyl N-phenyl carbamate possess microtubule organizing centers of heightened stability

Seven soybean (Glycine max (L.) Merr.) cultivars zoned in forest-steppe and marshy woodlands of Ukraine: "Chernuatka", "Vasylkivska", "Kyivska-91", "Kyivska-27", "Marjana", "Chernobura" and "Altair" were established in vitro for somatic embryogenesis inducing. Cultivars "Marjana" (88%) and "Vasylkivska" (86%) demonstrated the highest embryogenic capacity among all the tested cultivars. During the further plant regeneration cultivars "Marjana" and "Kyivska-91" showed the best capacity to form adult plants despite the fact that embryogenic capability of the cultivar "Kyivska-91" was 71%. According to the obtained data three genotypes were selected for the further investigation of effective methods of biolictic transformation of ukrainian cultivars.

[Evaluation of embryological potential of soybean cultivars zoned in forest, steppe, and marshy woodlands of Ukraine as essential stage for the further transformation].

Emets Ai

Papers

Bioinformatics Search for Plant Homologues of Ste20-like Serine/Threonine Protein Kinases

[Developing transgenic barley lines producing human lactoferrin using mutant alfa-tubulin gene as selective marker gene].

Effect of serine/threonine protein kinases and protein phosphatases inhibitors on mitosis progression in a synchronized tobacco BY-2 culture

Nicotiana sylvestris L. mutants resistant to isopropyl N-phenyl carbamate possess microtubule organizing centers of heightened stability

[Evaluation of embryological potential of soybean cultivars zoned in forest, steppe, and marshy woodlands of Ukraine as essential stage for the further transformation].