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V Z Tarantul

Publications and source records attributed to V Z Tarantul.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Effects of human immunodeficiency virus type 1 nef and tat genes on rat PC12 pheochromocytoma cells].

The regulatory genes nef and tat of the human immunodeficiency virus type 1 (HIV-1) were transferred into the rat pheochromocytoma cells (line PC12) under the control of the eukaryotic promoters. Proliferative activity of the PC12 cells transfected with the tat HIV-1 gene was substantially increased as compared to the control. Conversely, the nef gene introduced into the cultivated PC12 cell caused inhibition of their proliferative activity and formation of cell agglomerates resembling in morphology the multinuclear syncytial cells. Thus, our results suggest that the tat gene activates proliferation of the cultivated PC12 cells, whereas the nef gene inhibits proliferation of the same cells. We have obtained for the first time a direct indication for the possible role of the nef gene in formation of multinuclear T-lymphocyte and macrophage syncytium in HIV-1-infected patients. The HIV-1 nef and tat genes had no significant effect on the neuronal differentiation of the PC12 cells induced by the nerve growth factor (NGF).

Animals↗
PubMed1997

[Effects of the nef and tat genes of the human immunodeficiency virus type I on rodent cells in vivo and in vitro].

The tat and nef regulatory genes of the human immunodeficiency virus type I (HIV-1) under the control of eukaryotic promoters were transferred in vivo into mice and in vitro into rat cell cultures. The development was disturbed and adenocarcinomas of the lacrimal glands and pancreas appeared in transgenic mice carrying the HIV-1 tat gene. Transfection with the tat gene altered morphology and increased proliferative activity of Rat-2 pseudonormal cells. The tat gene also induced the formation of neoplastic foci in a primary rat embryo fibroblast culture. The results obtained showed that the HIV-1 tat gene can act as an oncogene and activate the proliferation of cultured cells. Cell proportions in peripheral blood and bone marrow were altered and mitogen-induced lymphocyte proliferation was decreased in transgenic mice carrying the HIV-1 nef gene. This gene also significantly suppressed proliferation but had no effect on morphology of Rat-2 cells. Thus, the HIV-1 nef gene appeared to suppress proliferation of various animal cells.

Animals↗
PubMed1993

Preferential extrachromosomal localization of exogenous DNA in transgenic silkworm Bombyx mori L.

Transgenic silkworms (Bombyx mori L.) were obtained by microinjection of plasmid pPrC-LTR1.5, which carris 1.5 DNA copies of Rous sarcoma virus (RSV) long terminal repeats (LTRs) inserted in the vector pBR322. The transgene was transmitted over the three generations obtained up to now. Most of the exogenous DNA failed to integrate into the genome and persisted as an extrachromosomal element that is subject to rearrangements. Plasmids carrying only part of the input DNA together with fragments of silkworm DNA were rescued from the transgenic animals. One of the rescued plasmids contained a sequence which belongs to a family of evolutionarily conserved repeated sequences.

Animals↗
PubMed1991

[Biological effect of human erythropoietin in transgenic mice].

Transgenic mice were obtained inheriting the human erythropoietin gene under the control of viral regulatory elements. The reliable difference in haematocrit, the content of haemoglobin and percentage of reticulocytes in peripheral blood were not revealed. The level of serum erythropoietin in transgenic mice is several fold higher than in control mice. The increased pool of erythroid cells was observed in the bone marrow of transgenic mice, especially of normoblasts (3-fold) and reticulocytes (4,5-fold).

Animals↗
PubMed1989

[Molecular and cytologic analyses of the transcription of evolutionarily conservative moderately repetitive sequences of vertebrate genomes].

Transcription of several families of moderately repeated sequences, conserved through the evolution of vertebrates, has been studied in different types of pigeon, chicken and mouse cells. It is shown both by hybridization with isolated RNA and by in situ hybridization that the families of repeats, dispersed in bird genomes and organized in clusters, are differentially expressed in pigeon erythroid cells with different degrees of specialization; in addition, they are transcribed in different types of chick embryo cells and on lampbrush chromosomes in chicken oocytes. Sequences homologous to these repeats were transcribed in different types of newborn mouse cells. Another family of conservative moderate repeats (family T1) dispersed in the mouse genome was also transcribed in a large variety of tissues in both new-born mice and chick embryos. A comparison of structural and transcription features of conservative moderate repeats represented in genomes of the number of vertebrates made it possible to regard them as "housekeeping" elements. The conservation in the evolution as well as the character of transcription of similar genome elements testify to their important role in the organism functioning at different stages of development.

Animals↗
PubMed1989

[New data on the type of structural changes in DNA of simian adenovirus SA7 microinjected into mouse zygotes].

The structure of the transgene has been analysed in a new series of experiments on the transfer of adenovirus SA7 DNA into the mice zygotes by microinjection technique. The previous data on SA7 DNA elimination from the genomes of different organs (sceletal muscles, heart, tail) have been confirmed and detailed for the F0 and F1 generations of transgenic animals. The left end of adenoviral genome has been shown to be predominantly transfered after microinjections of SA7 DNA into the mice zygotes.

Adenoviridae↗
PubMed1988

[Production of transgenic rabbits and mice carrying the gene for bovine growth hormone].

The results of experiments on the transfer of bovine gene for growth hormone into mice and rabbits are presented. The gene was transferred by the technique of microinjection into the zygote. In all cases transgene in rabbits occurred to be changed. In two transgenic mice the bovine growth hormone gene represented some tandem arranged copies. One of the mice had accelerated growth. This phenotypic changes is found to be inheritable.

Animals↗
PubMed1986

Rearrangements of microinjected recombinant DNA in the genome of transgenic mice.

Previously, mouse zygotes were microinjected with the recombinant plasmid pMA3, which contains the Herpes simplex virus thymidine kinase gene attached to the promoter region of the Rous sarcoma virus (Gazaryan et al. 1984a). In the present work the pMA3 fragment with the flanking genomic sequences was isolated from the DNA of one transgenic Fo mouse by the "plasmid rescue" technique. The rescued plasmid (pMAR1) lacked all virus-specific sequences and retained only some pBR322 sequences. The flanking region at one end of the integrated pBR322-specific fragment contained a highly conserved mouse repetitive sequence. The possible mechanisms of rearrangement of foreign DNA in germ line cells are discussed.

Animals↗
PubMed1986

[Transcription, in frog oocytes and transgenic mice, of recombinant plasmids with long terminal repeats of retrovirus proviruses].

RNA-DNA hybridization was used to study the transcription efficiency of the genes controlled by the long terminal repeats (LTR) from two different retroviral proviruses (exogenous provirus of the chicken Rous sarcoma virus and endogenous xenotropic provirus of the mouse). The oocyte nuclei of Xenopus laevis and the liver of transgenic mice were used as the transcription systems. The transcription efficiency of genes with the above mentioned promoters was shown to be roughly the same for both systems. Thus, the LTR of two proviruses of different origin possess the promoters of comparable strength and do not show any marked tissue or species specificity.

Animals↗
PubMed1984

Microinjection of simian adenovirus SA7 (C-8) DNA into the mouse zygotes: differential distribution of viral DNA in organs.

A simian adenovirus SA7 (C-8) DNA was microinjected into fertilized mouse eggs. Thirty-five mice derived from eggs injected with SA7 DNA were screened for the presence of the adenovirus genome in their liver DNA. Eighteen of these mice contained the virus-specific sequences. SA7 DNA was detected in some tissues, but in all cases, viral sequences were absent from muscle and heart DNA. Viral DNA was inherited by 50-70% of the next generation. One mouse that contained about 1 copy of SA7 DNA per haploid genome has been shown to pass it on to five generations, although the integrated viral DNA sustained a considerable structural change between F1 and F3. RNA analysis in various organs of 12 mice has shown the transcription of SA7 DNA to be very infrequent: only in the kidney of one mouse and in the spleen of another did RNA contain SA7-specific sequences.

Adenoviridae↗
PubMed1982

[Size and organization of repetitive sequences in pigeon genome].

Organization of sequences in pigeon genome and the spectrum of their repetition frequencies were studied by means of DNA/DNA reassociation. Reassociation of 125I-labelled DNA fractions isolated from pigeon total DNA attested the presence of rare repetitions with an average of 50 copies within a gaploid genome. The disposition of repetitive and unique sequences was studied by reassociation of the labelled fragments of different length with an essential excess of short fragments of an unlabelled DNA. Additional evidence was provided by estimation of hyperchromicity and resistance to nuclease S1 of long DNA fragments, reassociated to the given C0t values. It was demonstrated that approximately one fourth of the pigeon genome consists of intermittent repetitive and unique sequences with individual elements of average length of 2 and 37 kb, respectively (1 kb = = 1000 nucleotide base pairs). A hypothetical organization of palindromic sequences in pigeon genome is discussed in terms of the dependence of the value of zero binding to hydroxyapatite on the fragment length.

Animals↗
PubMed1982

[Nucleotide sequence organization of nuclear DNA of wheat embryos].

The kinetic component composition of wheat embryo nuclear DNA was studied. It was shown that 32% of the genome consist of highly repetitive sequences. Intermediate repetitive sequences with repetitive frequency 1300 per genome constitute the bulk (52%) of the wheat embryo nuclear genome. The unique sequences constitute 12% of wheat embryo DNA. The individual families of intermediate repetitive and unique sequences were isolated; their reassociation kinetics were investigated and their kinetic complexity and repetition frequency were evaluated. Intermediate repetitive sequences 600-800 nucleotides in length were interspersed with unique sequences 800-1000 nucleotides long in the nuclear genome of wheat embryos. The linear relationship between the fragment length and the increasing amount of the zero-time binding DNA implies that 4% of the wheat embryos genome consists of palindromic sequences, which are clustered into groups.

Base Composition↗