TSitologiia i genetika最新文献

Precise chromosome segregation is vital for speciation and hybrid formation. The aim of the work was to study the chromosomes behaviour and inheritance of maternal and paternal genomes in Arabidopsis regenerants de-rived from in vitro cultured cells on the medium with PFFA. The Arabidopsis thaliana model hybrid between Columbia and Landsberg erecta ecotypes was developed, which chromosomes were easy to distinguish using the 12 SSLP selected markers. Also, the influence of PFFA on the callus formation and regeneration of plants was analysed. 20 regenerated plants cultured with PFFA were derived, three of which were shown to loss the heterozygosity in six loci by DNA markers analysis. Different models are certainly required to understand how and when the mechanisms leading to proper chromosome segregation are established in species and hybrids.

Recent genome-wide association studies (GWAS) demonstrated that genetic variation in intron 2 of fibroblast growth factor receptor 2 (FGFR2) was a novel risk for breast cancer. We investigated whether two SNPs rs1219648 and rs2981582 in intron 2 of FGFR2 were associated with the risk of breast cancer in Chinese women. A total of 340 female breast cancer patients and 400 normal age-matched controls were recruited. Two SNPs were genotyped using matrix-assisted laser desorption/ionization mass spectrometry. The two SNPs rs1219648 and rs2981582 showed no association with the risk of breast cancer. A subgroup analysis by menopausal status demonstrated that the distribution of rs2981582 T alleles, including CT and TT genotypes, was significantly higher in premenopausal patients compared with postmenopausal patients. The TT genotype in rs2981582 was more strongly associated with ER-positive than with ER-negative tumors by ER status analysis. Analysis by haplotypes showed that no haplotypes associated with breast cancer. The results showed no association between two SNPs, rs1219648 and rs2981582 and breast cancer risk, although in a stratified analysis rs2981582 strongly associated with premenopausal and ER-positive breast cancer patients in Chinese women.

In this study we presented data on the production of branched root hairs in the seedlings of A. thaliana under progressive water deficit. The overall production of branched hairs was quite high under stress conditions and amounted to 8,27 %. On the contrary, this form of root hairs was almost absent in the control group (0,27 %). The highest number of branched hairs was produced at the beginning of the stress action. Branched root hairs are quite uniform structures in the sense of their morphology. To solve the question how the branched hairs grow, the structure of actin cytoskeleton was explored. This structure was different in the root hair and in its branch, which is an indication that the hair stops its growth at the moment when the branching starts. We have also characterized the production of branched root hairs in hormonal mutants of Arabidopsis and found the involvement of auxin in this process.

The anabolic effects require brief exposures to higher than average PTH concentrations. The catabolic effects result from pathological conditions in which parathyroid glands secrete too much hormone continuously at a sustained level. The aim of the present study was observance of intermittent (I-PTH) and continuous (C-PTH) PTH 1-34 administration influence on bovine chondrogenic progenitor cells (CPC) differentiation. Alcian blue was used to determine proteoglycan accumulation in CPC monolayer cultures. Thus in plates containing CPCs in C-PTH media chondrogenic differentiation was indicated by intensive proteoglycan accumulation in extracellular matrix. CPCs monolayer cultured in osteogenic media were subjected to Alizarin Red staining for matrix mineralization detection. Intense staining was revealed in I-PTH cells in comparison with C-PTH plates. The data obtained by monolayer cultures histological staining were confirmed by PCR analysis.

The aim of the study was to evaluate the association between the angiotensin-converting enzyme ACE I/D (rs4340) polymorphism and DNA damage in pati-ents with essential hypertension (EH). The I/D polymorphism of ACE was determined by polymerase chain reaction in 170 male hypertensive patients and 64 normotensive blood donors. We used flow cytometry to determine the levels of cell death, micronuclei and accumulation of peripheral blood leukocytes in G1/G0, S, G2/M phases of the cell cycle. Additionally, the whole blood samples were incubated in vitro at 4 ºC for 24 h to investigate the genotype effects on the susceptibility of cells to DNA damage. We found lower frequency of cells in DNA synthesis S phase and higher levels of micronuclei in the hypertensive compared to normotensive group (p<0.05); increased formation of micronuclei was seen due to elevated micronuclei fre-quencies in patients with the ACE II genotype (p < 0.05), but not in ID or DD genotype carriers. Incubation of whole blood samples of normotensive individuals lead to the most active cell death (p < 0.05) and micronuclei formation (p > 0.05) in the II genotype carriers too. However, hypertensive patients displayed different cellular response to incubation-induced DNA damages in the ACE I/D genotype groups; after incubation, the frequencies of micronuclei were significantly higher in the DD genotype carriers (p < 0.05). To conclude, the study suggests that the ACE I/D polymorphism may contribute to mechanisms and intensity of DNA damages in hypertensive and normotensive individuals.

The effect of the low temperature (4 ºC) on the orga-nization of actin filaments (microfilaments) of cells of different growth zones of the root of Arabidopsis thaliana (L.) have been studied. It was found that cold treatment inhibits growth of the main root and gives its morphology, causing a large number of deformed (ectopic) root hairs in the zone of differentiation. The temporal relationship of the disorientation and the organization of actin filaments and the detected changes of growth and morphology of roots under conditions of cold factor is shown. It has been found that the most sensitive to the cold are actin filaments of root hairs, meristematic cells, cells of elongation zone, and all epidermal cells of the root zones of A. thaliana.

The mechanisms of diabetes-associated impairment of cellular immune defense and its regulation by vitamin D3 are not fully elucidated. The study was devoted to investigating the functional state of T-cell immunity as well as humoral immune activity in response to artificial immunization in experimental diabetes and after prolonged administration of vitamin D3. It was established that diabetes is characterized by a 2.3 times decrease in blood serum 25OHD3 content. Vitamin D3 deficiency was accompanied by the failures in proliferative activity of T-lymphocytes and alterations of the regulatory (CD4+-postive lymphocytes) and cytotoxic (CD8+-positive lymphocytes) cell subpopulations. It was found an increase in the content of phosphorylated p65 subunit of nuclear factor κB in total lysates of spleen T lymphocytes and its enhanced translocation to the nucleus. In addition, it was shown intensification of humoral IgG response to administration of recombinant diphtheria toxin subunit B. Revealed impairments in the cellular link of the immune system were associated with an increase in splenocytes apoptosis, which was detected by Annexin V-GFP ability to bind phosphatidyl serine that is specifically located on the outer surface of plasmalemma in apoptosis. Prolonged vitamin D3 treatment (within 2 months) in a dose of 20 IU/animal leads to normalization of the proliferative activity and the ratio of T-cell subpopulations, reduces the formation of phosphorylated subunit of NF-κB - p65 and contributes to a balanced secretion of IgG against artificial antigen. These changes were accompanied by a decrease in apoptotic events in the total population of splenocytes. Our findings suggest an important role of vitamin D3 in the regulation of the immune system abnormalities related to type 1 diabetes.

The development of chronic myeloid leukemia (CML) is the result of a reciprocal translocation between chromosomes 9 and 22 due to the emergence of Philadelphia chromosome. The product of this mutation is a hybrid oncoprotein Bcr-Abl. According to the results of mass spectrometric analysis, USP1 protein was identified as a potential candidate for interaction with the PH domain Bcr-Abl oncoprotein. Due to the deubiquitination properties, USP1 protein can prevent proteasomal degradation of Bcr-Abl oncoprotein in a cell and, consequently, contribute to its accumulation, and the progression of the disease. In this work, creating the genetic constructs, we detected the USP1 protein localization in the cell. Also, a nuclear colocalization of USP1 protein with PH domain of Bcr-Abl oncoprotein in HEK293T cells was shown. The results are important for understanding the implications of the Philadelphia chromosome emergence, and the development of new methods for CML treatment, since the recent techniques are not always effective due to the emergence of numerous mutations that cause drug resistance and relapse of the disease.

To study the influence of intraperitoneally injected extracellular ubiquitin on regeneration of leucopoiesis calculation of nuclear cell count in bone marrow and peripheral blood smearsstained withazure-eosin was performed. In the first, control group of animals inhibition of haematopoiesis achieved by means of 100 mg/kg cyclophosphamide LD50 50–200 mg/kg injection. Bone marrow and peripheral blood samples from the first group of rats had been taken at 24, 48, 72, 96 and 168 h points after injection of cytostatic. Animals of the second, test group were injected by 200 μg/ml ubiquitin 72 h later after cytostatic injection. Our experiments revealed that ubiquitin makes corrections in regeneration of leucopoiesis and leads to normalisation of the process. Ubiquitin regulates stem cell activity, normalizes the release of functional cells into bloodstream, supposedly retains progenitor cells in zones of differentiation and maturation, and restores the nuclear cell ratio in PB and BM. We suppose that obtained results are important for elucidation of new pathways of ubiquitinylation and give us possibilities to find new therapeutics for regeneration of leucopoiesis that is very essential for treatment of radiated bone marrow and chemotherapeutic side effects in cancer patients.

In the previous cytogenetic study of new human stem cell line 4BL at the 205th passage we observed the ploidy of chromosomal set and regular aberrations. To investigate the nature of monosomy of certain chromosomes the array CGH and FISH analyses have been used. The aberrations of chromosomes have been identified in all the cases of monosomies previously revealed by G-banding. The largest changes of the DNA balance have been detected in the chromosomes 2, 4, 10, 13 and 17. The probable cause of the monosomies of chromosomes 4, 10, 13 and 17 is massive loss of the genetic material. The monosomy of the second chromosome pair is caused by significant transformation one of the homologs in a type of numerous duplications and formation of der(2)t(2;?)(q21;?). Due to application of array CGH the regions of the structural aberrations of the chromosomes 2, 4, 10, 13 and 17 have been concretized, what permitted to perform their clarifying identification by multicolored FISH method. The results obtained by us confirm the hypothesis about coordinated appearance of the deletions and duplications and their stabilization impact on the transformed chromosomes.