ABSTRACT
References are analyzed concerning production and studying of transgenic plants tolerant to various kinds of abiotic stresses; mechanisms of plant protection against stresses; the genes encoding the great spectrum of compounds giving to plants ability to survive in conditions of the stresses considerably repressing development and even lethal for control plants.
Subject(s)
Adaptation, Physiological/genetics , Plants, Genetically Modified , Stress, Physiological/genetics , Transgenes , Plant Physiological Phenomena/genetics , Plant Proteins/genetics , Plants, Genetically Modified/enzymology , Plants, Genetically Modified/genetics , Plants, Genetically Modified/physiologyABSTRACT
The average number of aberrations per aberrant cell was concluded to carry out information on chromosome instability peculiarities induced by different mutagens as it was shown in our previous work. The purpose of the current study was to present comparative analysis of intercellular distribution of number of aberrations and their theoretical approximations. Distribution of numbers of aberrations per cell in Allium cepa L. and Allium fistulosum L. root tip cells induced by different mutagenic factors (gamma-irradiation, thiotepa, formaldehyde and seed aging) have been studied. The results were approximated to theoretical Poisson, geometric and negative binomial distributions. The intercellular distribution of aberrations did not correspond to any of the used theoretical distributions when A. cepa seeds were gamma-irradiated. There was some, but not regular, accordance with theoretical distributions when chemical mutagens thiotepa in A. cepa and formaldehyde in A. fistulosum and seed aging in both species were evaluated. During seed aging frequency of aberrant cells increased more quickly in A. fistulosum in comparison with A. cepa.
Subject(s)
Allium/genetics , Chromosomal Instability/genetics , Chromosomes, Plant/genetics , Gamma Rays , Meristem/genetics , Mutagens/toxicity , Allium/drug effects , Allium/radiation effects , Chromosome Aberrations/statistics & numerical data , Meristem/drug effects , Meristem/radiation effects , Models, Genetic , Poisson DistributionABSTRACT
Analysis of chromosome instability (CI) is of great importance in view of pollution of the environment by genotoxic factors. Frequency of aberrant cells, spectrum of chromosome aberrations, damages of aberrant cell and distribution of aberrations in the cells are the most conventional parameters of CI. We have carried out the comparative analysis of the frequency of aberrant cells and the dynamics of aberrant cell damages induced by different mutagenic factors (alpha-irradiation from 241Am, gamma-irradiation from 60Co and tioTEPA) in Allium-test. This comparative analysis denotes that the studied parameters have different dynamics characterizing different mechanisms of CI in Allium cepa L.
Subject(s)
Chromosome Aberrations , Mutagens , Allium/drug effects , Allium/genetics , Allium/radiation effects , Alpha Particles/adverse effects , Americium/toxicity , Antineoplastic Agents, Alkylating/radiation effects , Cobalt Radioisotopes/radiation effects , Dose-Response Relationship, Drug , Dose-Response Relationship, Radiation , Gamma Rays/adverse effects , Thiotepa/radiation effectsABSTRACT
The purpose of this study was to elucidate the genome damage induced by 241Am-irradiation using different parameters of cytogenetic evaluation in Allium-test. The root tip cells test-system for the cytogenetic effects studying was used. 241AmCl3 of different concentrations was used (1.5 x 10(-9)-1.5 x 10(-7) g/l). Water solution-to-plant transfer factor for 241Am was found to be 0.18 +/- 0.04. The internal doses of 241Am accumulated during germination were 0.37-37.00 cGy. The impact of 241Am-irradiation was evaluated on the mitotic index (MI), the yield of aberrant anaphases (AA), the distribution of chromosome aberrations number in cells and the average level of lesion of aberrant cell (LAC). Probably all these parameters are differ in sensitivity to damage factor, but only some changes in MI was revealed. It is supposed, that the absence of any changes in the distribution of chromosome aberrations number in cells and the average level of LAC in 241Am-irradiated cells confirm the absence of significant 241Am-impact on chromosomes, as the alpha-irradiation should cause significant damages in chromosomes. Although solutions of 241Am were high-concentrated, the seedlings didn't accumulate high internal doses. It appears the distribution of 241Am is a significantly heterogeneous hence it is possible the absorbed doses in nuclei can't reach the level necessary for revealing of cytogenetic effects.
