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Transgenic tobacco plants overexpressing the choline oxidase gene from A. globiformis showed an increase in resistance at the level of primary and secondary biosynthesis of metabolites, removing the damage characteristic of salinity and stabilizing the condition of plants. We used 200 mM NaCl, which inhibits the growth of tobacco plants at all stages of development. Leaves of transgenic and wild-type (WT) plants Nicotiána tabácum were used for biochemical, cytological and molecular biological analysis. However, for transgenic lines cultivated under normal conditions (without salinity), we noted juvenile characteristics, delay in flowering, and slowing down of development, including the photosynthetic apparatus. This caused changes in the amount of chlorophyll, a delay in the plastid grana development with the preservation of prolamellar bodies. It also caused changes in the amount of sugars and indirectly downstream processes. A significant change in the activity of antioxidant enzymes and a change in metabolism is probably compensated by the regulation of a number of genes, the expression level of which was also changed. Thus, the tolerance of transgenic tobacco plants to salinity, which manifested itself as a result of the constitutive expression of codA, demonstrates an advantage over WT plants, but in the absence of salinity, transgenic plants did not have such advantages due to juvenilization. [ABSTRACT FROM AUTHOR]

Secondary metabolites of aromatic plants are used in many health applications as drugs, pheromones, insecticides, fragrances, and antioxidants. Due to the huge commercial demand for these secondary metabolites, the need to overcome the insufficient productivity of aromatic plants has become a significant challenge. Plant breeding is a traditional, labor-intensive, and limited method to improve the ability of aromatic plants to produce secondary metabolites. Modern methods of biotechnology, including genetic engineering and genome editing, can be useful and cost-effective in improving aromatic plants, as they can increase the efficiency of obtaining plants with high productivity and the creation of resistant forms and breeding lines. This review illustrates the importance of developing methods for the modification of aromatic plants belonging to different families, with a predictable quality, resistance to adverse factors and pests, and intensive growth and high yields and productivity of valuable essential oils. Particular attention is paid to successful examples of the modification of aromatic plants, applied methods, and principal approaches [ABSTRACT FROM AUTHOR]

In this study the transgenic lines (TLs) of tobacco (Nicotianatabacum L.), which overexpress the heterologous gene encoding the bacterial enzyme choline oxidase were evaluated. The goal of our work is to study the effect of choline oxidase gene expression on the sensitivity of plant tissues to the action of NaCl. The regenerative capacity, rhizogenesis, the amount of photosynthetic pigments and osmotically active compounds (proline and glycine betaine) were assessed by in vitro cell culture methods using biochemical and morphological parameters. Transgenic lines with confirmed expression were characterized by high regeneration capacity from callus in the presence of 200 mmol NaCl, partial retention of viability at 400 mmol NaCl. These data correlated with the implicit response of regenerants and whole plants to the harmful effects of salinity. They turned out to be less sensitive to the presence of 200 mmol NaCl in the cultivation medium, in contrast to the WT plants. [ABSTRACT FROM AUTHOR]

Crystal-bearing cells or idioblasts, which deposit calcium oxalate, are located in various tissues and organs of many plant species. The functional significance of their formation is currently unclear. Idioblasts in the leaf parenchyma and the development of crystal-bearing cells in the anther tissues of transgenic tomato plants (Solanum lycopersicon L.), expressing the heterologous FeSOD gene and which showed a decrease in fertility, were studied by transmission and scanning electron microscopy. The amount of calcium oxalate crystals was found to increase significantly in the transgenic plants compared to the wild type (WT) ones in idioblasts and crystal-bearing cells of the upper part of the anther. At the same time, changes in the size and shape of the crystals and their location in anther organs were noted. It seems that the interruption in the break of the anther stomium in transgenic plants was associated with the formation and cell death regulation of a specialized group of crystal-bearing cells. This disturbance caused an increase in the pool of these cells and their localization in the upper part of the anther, where rupture is initiated. Perturbations were also noted in the lower part of the anther in transgenic plants, where the amount of calcium oxalate crystals in crystal-bearing cells was reduced that was accompanied by disturbances in the morphology of pollen grains. Thus, the induction of the formation of crystal-bearing cells and calcium oxalate crystals can have multidirectional effects, contributing to the regulation of oxalate metabolism in the generative and vegetative organs and preventing fertility when the ROS balance changes, in particular, during oxidative stresses accompanying most abiotic and biotic environmental factors. [ABSTRACT FROM AUTHOR]

Simple Summary: We analyzed the morphological changes in root tip cells caused by the application of iso-osmotic NaCl and Na2SO4 solutions to tomato plants harboring an introduced superoxide dismutase gene. To study the roots of tomato plants cultivar Belyi Naliv and FeSOD-transgenic line, we examined the distribution of reactive oxygen species and immunodetection of α-tubulin. The differences in the microtubules cortical network between wild type and transgenic plants without salinity were detected. The differences were found in the cortical network of microtubules between control and transgenic plants in the absence of salt stress. While an ordered microtubule network was revealed in the root cells of wild type tomato, no such degree of ordering was detected in transgenic line cells. The signs of microtubule disorganization in root cells of wild type plants were manifested under the NaCl and Na2SO4 treatment. On the contrary, the cytoskeleton structural organization in the transgenic line cells was more ordered. In addition, the formation of atypical tubulin polymers was observed in response to salt stress. Changes in cell size, due to both vacuolization and impaired cell expansion in columella zone and cap initials, were responsible for the root tip tissue modification. Various abiotic stresses cause the appearance of reactive oxygen species (ROS) in plant cells, which seriously damage the cellular structures. The engineering of transgenic plants with higher production of ROS-scavenging enzyme in plant cells could protect the integrity of such a fine intracellular structure as the cytoskeleton and each cellular compartment. We analyzed the morphological changes in root tip cells caused by the application of iso-osmotic NaCl and Na2SO4 solutions to tomato plants harboring an introduced superoxide dismutase gene. To study the roots of tomato plants cultivar Belyi Naliv (WT) and FeSOD-transgenic line, we examined the distribution of ROS and enzyme-linked immunosorbent detection of α-tubulin. In addition, longitudinal sections of the root apexes were compared. Transmission electronic microscopy of atypical cytoskeleton structures was also performed. The differences in the microtubules cortical network between WT and transgenic plants without salt stress were detected. The differences were found in the cortical network of microtubules between WT and transgenic plants in the absence of salt stress. While an ordered microtubule network was revealed in the root cells of WT tomato, no such degree of ordering was detected in transgenic line cells. The signs of microtubule disorganization in root cells of WT plants were manifested under the NaCl treatment. On the contrary, the cytoskeleton structural organization in the transgenic line cells was more ordered. Similar changes, including the cortical microtubules disorganization, possibly associated with the formation of atypical tubulin polymers as a response to salt stress caused by Na2SO4 treatment, were also observed. Changes in cell size, due to both vacuolization and impaired cell expansion in columella zone and cap initials, were responsible for the root tip tissue modification. [ABSTRACT FROM AUTHOR]

The study was devoted to morphological and cytoembryological analysis of disorders in the anther and pollen development of transgenic tomato plants with a normal and abnormal phenotype, which is characterized by the impaired development of generative organs. Various abnormalities in the structural organization of anthers and microspores were revealed. Such abnormalities in microspores lead to the blocking of asymmetric cell division and, accordingly, the male gametophyte formation. Some of the non-degenerated microspores accumulate a large number of storage inclusions, forming sterile mononuclear pseudo-pollen, which is similar in size and appearance to fertile pollen grain (looks like pollen grain). It was discussed that the growth of tapetal cells in abnormal anthers by increasing the size and ploidy level of nuclei contributes to this process. It has been shown that in transgenic plants with a normal phenotype, individual disturbances are also observed in the development of both male and female gametophytes. The reason for the developmental arrest of some ovules was the death of endosperm at different stages of the globular embryo. At the same time, noticeable hypertrophy of endothelial cells performing a secretory function was observed. In the ovules of transgenic plants with abnormalities, the endothelium forms a pseudo-embryo instead of the embryo sac, stimulating the development of parthenocarpic fruits. The data obtained in this study can be useful for a better understanding of the genetic and molecular mechanisms of cytoplasmic male sterility and parthenocarpic fruit development in tomatoes. [ABSTRACT FROM AUTHOR]