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N S Zhdanova

Publications and source records attributed to N S Zhdanova.

At least 19 recordsLinked to original sources
PubMed2006

Identification of all pachytene bivalents in the common shrew using DAPI-staining of synaptonemal complex spreads.

A major problem in studies of synaptonemal complexes (SC) is the difficulty in distinguishing individual chromosomes. This problem can be solved combining SC immunostaining with FISH of chromosome-specific sequences. However, this procedure is expensive, time-consuming and applicable only to a very limited number of species. In this paper we show how a combination of SC immunostaining and DAPI staining can allow identification of all chromosome arms in surface-spreads of the SC of the common shrew (Sorex araneus L.). Enhancement of brightness and contrast of the images with photo editing software allowed us to reveal clear DAPI-positive and negative bands with relative sizes and positions similar to DAPI landmarks on mitotic metaphase chromosomes. Using FISH with DNA probes prepared from chromosome arms m and n we demonstrated correct recognition of the chromosomes mp and hn on the basis of their DAPI pattern. We show that the approach we describe here may be applied to other species and can provide an important tool for identification of individual bivalents in pachytene surface-spreads.

Animals↗
PubMed2006

Comparative mapping of cattle chromosome 19: cytogenetic localization of 19 BAC clones.

Here we present the results of fluorescent in situ hybridization (FISH) mapping of a set of cattle BAC clones preselected for assignment on cattle chromosome 19 (BTA19). The BAC clones were anchored to human chromosome 17 (HSA17) sequences by BLASTn similarity search of cattle BAC-ends against the human genome sequence (NCBI build 33). Five blocks of homologous synteny were defined in the comparative map of BTA19 and HSA17 built with FISH data and the human genome coordinates. The positions for four evolutionary breakpoints in the bovine and human chromosomes were identified. Comparison of the FISH comparative map with previously published comparative RH, physical, and cytogenetic maps of BTA19 did not reveal major conflicts and allowed for the extension of the boundaries of homology between BTA19 and HSA17. Comparative analysis of HSA17, BTA19, and mouse chromosome 11 (MMU11) demonstrates that most likely mice retain the ancestral organization of the synteny group, and both cattle and human chromosomes underwent several major internal rearrangements after the divergence of Primates, Rodentia, and Cetartiodactyla.

Animals↗
PubMed2004

[The structure of a conserved region of porcine genome, represented in human genome by chromosome 17].

Radiation mapping of nine genes (H3F3B, HLR1, MYL4, STAT5B, THRA1, TOP2A, MCP1, NF1, and MPO) to porcine chromosome 12 was carried out. Also, subchromosomal location of the NF1 gene along with the two loci containing the DNA sequences homologous to the DNA of the two human BAC clones was determined. The NF1 position was ascertained via microdissection of chromosome 12 with subsequent PCR amplification of the gene fragment with specific primers. BAC clones were mapped using FISH. Comparative analysis of the gene order in porcine chromosome 12 and in the homologous human chromosome 17 was performed. It was demonstrated that the gene orders in these chromosomes differed relative to the position of the MPO gene.

Animals↗
PubMed2002

[Genome radiation hybrid mapping: summary and future directions].

Genome mapping by means of radiation-induced interspecific cell hybrids is a direct way to localize both high- and low-polymorphic nucleotide sequences, including gene sequences, on animal chromosomes. Using radiation hybrid panels either individual chromosomes and loci or entire genome can be mapped. This efficient approach makes it possible to reach high resolution of markers (up to 100 bp) as well as unify the mapping language. Due to electronic means of communication, the same experimental material can be used in numerous laboratories to provide high-resolution extended genomic maps saturated with markers. Radiation hybrid mapping is a powerful tool for analysis of complex genome structure. Using radiation hybrid maps permitted verification of regions of chromosome homeology in various species and detection of regions with conserved sequence and conserved gene order. Identification of these regions is extremely important for understanding evolution of species karyotypes and for making use of positional cloning to isolate genes responsible for commercial traits as well as genes involved in hereditary human diseases.

Animals↗
PubMed2001

[Radiation mapping of the short arm of swine chromosome 2].

In recent years, maps of mammalian genomes have been acquiring increasingly higher resolution. Integration of maps of different types has become possible. As a tool in integrating maps of mammalian genomes of different types, high-resolution mapping with radiation-induced hybrids (RH) is used. Here, we present an RH6000 map of the short arm of porcine chromosome 2. The map contains 15 microsatellites and five genes (for parathyroid hormone, lactate dehydrogenase A, myogenic factor, follicle-stimulating hormone beta, and calpain I). The RH panel was obtained on the basis of a hybrid cell line bearing the single porcine chromosome 2 against the background of mink chromosomes. The mean frequency of preserving markers examined in the panel was 18.3%. Integration of four genes in the panel and a comparison of gene order in homologous regions of human and porcine chromosomes are presented.

Animals↗
PubMed2001

[Use of PCR markers for mapping swine chromosome 12].

Using PCR analysis of pig-mink and pig-Chinese hamster hybrid cell lines and heterologous and homologous primers of various types, chromosomal and subchromosomal mapping of genes TOP2A, THRA, BRCA1, GAS, HLR1, MYL4, LIS1, MCP1, ENO3, CRYB1, P4HB, STAT5B, and H3F3B to pig chromosome 12 was carried out. The efficiency of using different types of heterologous primers for pig chromosome mapping was compared.

Animals↗
PubMed2000

Zoo-FISH with region-specific paints for mink chromosome 5q: delineation of inter- and intrachromosomal rearrangements in human, pig, and fox.

Comparison of evolutionarily conserved mammalian chromosomes homologous to human chromosome 17, performed with microdissected painting probes, revealed rearrangements inside these chromosomes in mink and pig and a disruption of this conserved region in the fox. Detection of a homologous region on an Iberian shrew chromosome showed the efficiency of microdissected painting probes for delineation of homologous chromosome regions in species belonging to orders that diverged at least 100 million years ago.

Animals↗
PubMed2000

Dog chromosome-specific paints reveal evolutionary inter- and intrachromosomal rearrangements in the American mink and human.

Forty chromosome-specific paint probes of the domestic dog (Canis familiaris, 2n = 78) were used to delineate conserved segments on metaphase chromosomes of the American mink (Mustela vison, 2n = 30) by fluorescence in situ hybridisation. Half of the 38 canine autosomal probes each painted one pair of homologous segments in a diploid mink metaphase, whereas the other 19 dog probes each painted from two to five pairs of discrete segments. In total, 38 canine autosomal paints highlighted 71 pairs of conserved segments in the mink. These painting results allow us to establish a complete comparative chromosome map between the American mink and domestic dog. This map demonstrates that extensive chromosome rearrangements differentiate the karyotypes of the dog and American mink. The 38 dog autosomes could be reconstructed from the 14 autosomes of the American mink through at least 47 fissions, 25 chromosome fusions, and six inversions. Furthermore, comparison of the current dog/mink map with the published human/dog map discloses 23 cryptic intrachromosomal rearrangements in 10 regions of conserved synteny in the human and American mink genomes and thus further refined the human/mink comparative genome map.

Animals↗
PubMed1998

[A new approach to the analysis of complex chromosomal rearrangements in cell hybrids].

The chromosomal complements of somatic cell pig-mink hybrids was determined by a new approach. This approach includes microdissection of metaphase chromosomes, generation of chromosome and region-specific DNA libraries, and fluorescence in situ hybridization of these libraries with pig lymphocyte chromosomes. The studied hybrid cells were shown to contain two small acrocentric chromosomes and a microchromosome of porcine origin. Identification of these chromosomes by differential GTG-staining was impossible. Chromosome isolation by a micromanipulation technique followed by DNA amplification in TOPO-DOP polymerase chain reaction provided chromosome-specific DNA libraries of the rearranged chromosomes. Based on these libraries, the labeled DNA probes were prepared and hybridized to pig chromosomes. This allowed us to determine the origin of the material contributing to the hybrid cell chromosomes. One of these chromosomes contained five pig chromosomal regions: 15cen-q2; 6q21-q23; 13q21; 13q22; 7q25-qter, while the other contained the following pig chromosomal regions: 4p12-p13; 16q12-q14; 12pter-p15. The microchromosome contained the Xp11-Xq11 region. The minimal size of the revealed chromosomal regions was about 3 to 4 x 10(6) bp. Segregation analysis of the thymidine kinase gene 1 (TK1), which was earlier localized to the pig 12p region, and the hybrid cell pig chromosomes in the hybrid subclones suggested that TK1 gene can be assigned to 12p15-pter. The results obtained demonstrate the efficiency of the applied approach in its detailed and reliable description of complex chromosomal rearrangements in hybrid clones, when differential chromosome staining failed to identify these chromosomes.

Animals↗
PubMed1998

[Chromosome localization and analysis of synteny analysis of some genes in swine, cattle, and sheep (Artiodactyla)].

Using the hybrid cell lines pig-American mink, cow-American mink, and sheep-American mink, the localization of some genes included in a large conservative block localized on human chromosome (chr) 17 was performed by means of electrophoresis of proteins and Southern blot hybridization. Genes NF1, RARA, PRKCA, and ERBB2 were assigned to chr 12 in swine; TK1 and UMPH2, to chr 19 in cattle; and TK1, UMPH2, and PEPA, to chr 11 in sheep. The conserved synteny of these genes in three representatives of the order Artiodactyla was shown.

Animals↗
PubMed1997

Scheduled perturbation in DNA during in vitro differentiation of mouse embryo-derived cells.

Studies of sister chromatid exchanges (SCE) and recombination rate of certain minisatellite DNAs have demonstrated that their levels are considerably higher during the preimplantation stage than in latest developmental stages of embryos. It appeared likely that single-strand DNA breaks (SSB) may be relevant to both events during early development. With this in mind, we estimated SSB during in vitro retinoic acid (RA)-induced and spontaneous differentiation of mouse teratocarcinoma (EC) and embryonic stem (ES) cells. Using the method of nucleoid sedimentation and single-cell DNA electrophoresis, we have observed a dramatic increase in the SSB during the first 2-4 mitoses after beginning of differentiation of EC cells, followed by a gradual return to the basal level characteristic of undifferentiated cells. The increase in the SSB was manifested as the appearance of mass nucleoids with slow sedimentation rates, as well as the low-weight mass fragments in DNA patterns of most cells. We concluded that not less than half of genomic DNA has been nicked at the early steps of differentiation. The decrease in SSB level was observed in spite of continuing differentiation, as judged by embryonic antigens and morphological criteria. Also, the increase in the SCE level coincided with that of SSB, possibly being its consequence. The scheduled "surge" of SSB may be the earliest event in commencing differentiation at steps without a phenotypic manifestation.

Animals↗
PubMed1994

Characterization of pig-mink cell hybrids: assignment of the TK1 and UMPH2 genes to pig chromosome 12.

By fusion of thymidine kinase-deficient mink cells with pig leukocytes, a new type of cell hybrid was produced. It was demonstrated that pig chromosomes segregate in pig-mink hybrids and that hybrid cells contain no cytologically visible rearrangements between the chromosomes of parental species, or chromosome fragmentation. With a set of subclones of two primary hybrid clones, the genes for thymidine kinase-1 (TK1) and uridine 5'-monophosphate hydrolase-2 (UMPH2) were assigned to pig Chromosome (Chr) 12. A cell line with a single pig Chr 8 on the background of mink chromosomes was established. This clone could serve as a source of DNA for building a chromosome-specific library of pig Chr 8. The data obtained suggest that pig-mink cell hybrids can be used for mapping of pig chromosomes.

5'-Nucleotidase↗
PubMed1994

[Study of protein products of gene expression in cells with altered chromosome sets for genetic mapping].

Two-dimensional electrophoresis was used for analyzing proteins in hybrid cells that contained single human chromosomes (chromosome 5, chromosome 21, or chromosomes 5 and 21) against the background of the mouse genome. By comparing the protein patterns of hybrid and parent cells (about 1000 protein fractions for each kind of cell), five fractions among proteins of hybrid cells were supposedly identified as human proteins. The genes of two of them are probably located on chromosome 5, and those of other three, on chromosome 21. Moreover, analysis of proteins in fibroblasts of patients with the cri-du-chat syndrome (5p-) revealed a decrease in the content of two proteins, as compared with those in preparations of diploid fibroblasts. This fact was regarded as evidence that two corresponding genes are located on the short arm of chromosome 5. Methodological problems associated with the use of protein pattern analysis in cells with altered chromosome sets for the purposes of genetic mapping are discussed.

Animals↗