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O L Polianovskiĭ

Publications and source records attributed to O L Polianovskiĭ.

At least 19 recordsLinked to original sources
PubMed2003

[Regulation of human oct-1 gene transcription involves two promotors].

Transcription initiation of human Oct-1 transcription factor-encoding gene involves two promoters, 1U and 1L, located at a substantial distance (about 100 kb) apart. The structure of these promoters and the adjacent sequences is different. Specifically, the 1U sequence is GC-rich, while the 1L sequence is AT-rich. Correspondingly, more than 25 GC-rich Sp1 cis-elements were localized within the 1U region, while in the 1L sequence nearly equal amount of homeo-specific NTAATNN sites along with two ATGCAAAT octamers were found. Analysis of transfection of recombinant plasmids, carrying the promoter fragments with or without enhancer indicated that expression from the 1L promoter was tissue-specific. In nonlymphoid HEK293 cells efficiency of transcription from the 1U promoter was several times higher than that from the 1L promoter. Another expression pattern was observed at transfection of the same constructs into Raji lymphoid cells. In this case the level of transcription from the L promoter (fragment L2) at the presence of external enhancer was higher than that from the fragments containing the 1U promoter. It was shown that the distal regions of 1U and 1L were capable of silencing activity. In Raji cells enhancer completely overcomes the activity of U silencer, but only partly overcomes the activity of L silencer. Our data on the interaction of two promoters with the enhancer and silencer in different cell types point to fine tissue-specific regulation of the oct-1 gene expression, especially in lymphatic cells.

5' Flanking Region↗
PubMed1990

[A new expressible VH-gene of the 36-40 family participates in the biosynthesis of antibodies against swine transferrin].

The expressible allelic variant of immunoglobulin heavy chain genes locus from hybridoma PTF-02 is localized in the 17 kb Bgl II fragment of DNA. The structure of VDJh 3 exon and flanking regions was investigated. The 1101 bp fragment was sequenced. It contains transcription regulatory sequences (cd and TTAAAT-box), the leader exon with internal intron (L), the Vh exon, D and Jh 3 segments. The Vh exon has unusual for immunoglobulin genes the first codon-threonine codon. It was shown that expressible in hybridoma PTF-02 Vh gene (Vh TF) represents and earlier unknown gene of the mouse 36-60 Vh family. This conclusion was made after the comparison of Vh TF exon structure and its 5'-region physical map with the other genes of the 36-60 family.

Amino Acid Sequence↗
PubMed1988

[Characteristics of the effect of Ca/Mg-dependent endonuclease from cell nuclei of human lymphocytes on J kappa-cluster of immunoglobulin genes].

The cleavage of the murine J kappa-segments by purified Ca/Mg-dependent endonuclease was studied. The enzyme was shown to cleave specifically the J kappa-segments introducing the double strand breaks in 5'-regions of the J kappa-genes. The number of thus generated discreet fragments does not change during incubation. Specificity of the enzyme is not changed by substitution of Ca/Mg for Mn. The enzyme activity is inhibited by 0.1 M NaCl as well as its specificity. Comparison of the enzyme with the known nuclease activities that cleave specifically the J kappa-segments demonstrated that the activities of the latter are determined by Ca/Mg-dependent endonuclease. The results suggest the possible participation of Ca/Mg-dependent endonuclease in Ig-genes recombination.

Animals↗
PubMed1988

[Factors interacting with promoter region of immunoglobulin genes. Determination of the binding site boundaries].

The nuclear extracts of plasmacytomas producing antibodies were found to contain factors which formed complexes with the promoter fragment of the gene for immunoglobulin kappa-chains. The corresponding complexes found in the extracts of nonlymphoid cells had a different mobility. Two approaches were proposed for determining the boundaries of the region necessary for protein factors to be bound to DNA using nuclease Ba131. A 5'-ATTTGCAT-3' octanucleotide sequence was shown to be necessary for interaction with the protein nuclear factor in the studied plasmacytoma lines. The protein completely lost its affinity if at least one nucleotide was removed or substituted at the 5'- or 3'-end of this sequence. The procedures proposed for determining the precise boundaries of the sequence necessary for protein binding to DNA do not require a preliminary protein purification. The principles on which the procedures are based, set no limitations to their application to other systems used for studying the interaction of proteins with DNA.

Animals↗
PubMed1987

[Regulation of transcription of immunoglobulin kappa genes in Xenopus laevis oocytes].

Recombinant plasmids containing the immunoglobulin kappa gene with deletions in the 5' and 3' regions of the gene having different position and orientation of the enhancer element were constructed. The plasmids were incubated with cell-free extracts prepared from lymphoid and non-lymphoid cells, and then injected into the nuclei of Xenopus laevis oocytes. Tissue-specific transcription of the V kappa gene was shown to be under control of factor(s) existing in lymphoid cells. The data reported in this paper allow to suggest that, along with the positive transcription control regions located in the 5' region of the gene and in the J-C intron, there is also a negative control region situated in the J-C intron as well. Possible role of the tissue-specific factors from lymphoid cells is to abolish the negative control.

Animals↗
PubMed1987

[Factors of tissue-specific transcription of immunoglobulin kappa genes].

Proteins TIF1 and TIF2 with mol mass 90 and 94 kD, respectively, were found in myeloma cells. They bind to the promoter region of the kappa genes. Protein TIF1 was found in nonlymphoid cells (HeLa, liver cells). From myeloma MPOC21 a fraction was isolated enriched 400 fold with TIF2 by fractionation on ion-exchangers DE52 and P11 and hydroxylapatite. The purified protein protected the DNA site that contained 30bp including the conservative sequence TNATTTGCAT located upstream of the kappa gene promoter against the action of DNAase. Addition of the purified factor to the extract from HeLa cells increased several fold the efficiency of transcription and corrected the initiation of transcription.

Animals↗
PubMed1986

[Regulator sequences in the kappa-chain gene expressed in the hybridoma PTF.02].

Two kappa genes, one (5.7 kb) from parental myeloma cells that were used for fusion, and the other (7.5 kb) from lymphocytes have been detected in the genome of PTF.02 hybridoma. Functionally important regions of the second gene were sequenced. In the 5'-region, positions and nucleotide sequences of the L-fragment, TAATA- and CAAT-boxes were established. Deca (dc)- and pentadecanucleotide (pd) sequences, obligatory for effective transcription of Kappa genes, were localized at the distance of 91 and 118 bp from the ATG initiating codon of the leader sequence. Together with a true pd, a shadow pd sequence was localized. This sequence was overlapped with the first sequence and shifted by one helical twist. The structure of the region of the enhancer localization was established. Comparison of this sequence with known consensus of the papova virus enhancer allows us to suggest the following structure of the enhancer core for kappa chains: TGTGGCTAA... 10 bp... TGTGGTTA. In the kappa gene under study, the variable fragment is linked to the J5 segment. In the latter, a point mutation C----G was found, to which a conservative substitution Ala - Gly in a hypervariable region of the chi-chain should correspond. Somatic mutations were also observed within the intron region adjacent to the J5 segment.

Animals↗
PubMed1982

[Construction and selection of bacterial clones hybridized with the mRNA of a light-chain immunoglobulin].

The copy-DNA was synthesized on the mRNA fraction which was isolated from MOPC 21 mice myeloma by reverse transcription. This copy was completed with another chain without adding the exogenous primer, with the aid of the Klenov fragment of DNA polymerase I. After treatment of the double-stranded pin DNA with endonuclease S1, the poly(dA) sequences were built up using terminal deoxynucleotidyl transferase. The building up of the poly(dT) sequences at the DNA 3'-termini of pBR322 plasmid previously treated with BamHI was performed in a similar way. The average length of connecting polynucleotide sequences was 50 nucleotides. After annealing and transformation of the cells with Escherichia coli hybrid plasmids, selection of clones was made for ApRTcS phenotype. Further, we applied a stepwise selection of clones by means of increasing the specificity: colony hybridization, quantitative hybridization of the excess of plasmid DNA with (32P)-cDNA and hybridization of plasmid DNAs with mRNA units which were transferred from electrophoregrams to the diazo-papers. As a result, bacterial clones were selected which contained gene fragments showing the ability to hybridize with the RNA fraction characterized by mRNA mobility of the light-chain immunoglobulin G.

Animals↗
PubMed1982

[Analysis and properties of a bacterial clone containing a gene fragment of an immunoglobulin L chain].

Restriction analysis of hybrid plasmids from a number of clones allowed to screen out the plasmid p8-1. A detailed analysis of this plasmid and that of the inserted DNA was made using HhaII, AluI, Sau96I, Sau3A, MspI and BspI restriction endonucleases. The results demonstrated that the inserted DNA corresponds to the 3'-nontranslated region and to a portion of the C fragment of the light-chain immunoglobulin gene. Establishing the partial structure of the recombinant plasmid exhibited a complete coincidence of the inserted DNA 3'-terminus and the primary structure of the light-chain mRNA synthesized by MOPC-21 myeloma cells. This sequence corresponds to the amino acid sequence in the light-chain constant region (207-214 residues). The analysis of p8-1 plasmid showed that nucleotides of pBR322 plasmid at positions from 376 to 618 were deleted. The deletion might be predetermined by the plasmid property to be amplified more readily than all the other hybrid plasmids which were not deleted.

Animals↗
PubMed1976

[A proteolytic enzyme bound to the aspartate transaminase of swine heart cytosol].

Purified preparations of aspartate transaminase from pig heart cytosol contain a tightly bound proteolytic enzyme (approximately 2, 5%). The enzyme was separated from aspartate transaminase by gel-filtration on Sephadex G-100 in the presence of sodium dodecyl sulfate and by affinity chromatography on the column with Sepharose, containing covalently bound denaturated aspartate transaminase. Protease has a pH optimum of 9.0 and molecular weight of about 23.000-25.000. The proteolysis rates of different subforms of aspartate transaminase depend on their denaturation lability. A more stable choloenzyme is split at a slower rate than the apoenzyme. An enriched preparation of protease was also shown to split glutamate decarboxylase from E. coli and had no effect on cysteinlyase from hen egg, as well as on lactate dehydrogenase and albumin.

Animals↗