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V Z Tarantul

Publications and source records attributed to V Z Tarantul.

87 records · Page 5Linked to original sources
PubMedDate not supplied

[Metabolically stable classes of nuclear messenger-like RNA. I. Detection and molecular characterization].

Two discreet in size molecular classes of metabolically stable messenger-like RNA molecules with sedimentation coefficientes about 28S and 18S have been revealed in the nuclei of pigeon bone marrow cells. The structural pecularities of 28S RNA class were investigated more carefully. It was shown to constitute the largest fraction of nuclear messenger-like RNA and is characterized by a GC/AU ratio 1.13. As pulse-labeled nuclear RNA, 28S stable nuclear RNA hybridizes with the unique and rare repeated DNA, it does not contain poly(A)-sequences and is found in a form of RNP particles with density of 1.41 g/sm3, tightly bound to chromatin.

Animals↗
PubMedDate not supplied

[Metabolically stable classes of messenger-like nuclear RNA. II. Existence of homology between the 28S fraction of nuclear RNA, giant non-polyadenylated molecules of heterogeneous nuclear RNA and polyadenylated molecules of cytoplasmic RNA].

The existence and extent of homology between the 28S fraction of messenger-like nuclear RNA on one hand, and giant (greater than 45S) molecules of heterogeneous nuclear RNA and various fractions of cytoplasmic RNA on the other hand were studied by the method of competitive hybridization. The results obtained lead to the conclusion that the poly(A)-subfraction of hnRNA molecules with the size of greater than 15 000 nucleotides contains molecules subjected to rapid but incomplete processing with the formation of chains approximately 5000 nucleotides long (approximately 28S), which are then stored in the nucleus for up to 30 hours. Later polyadenylated and non-polyadenylated molecules of cytoplasmic RNA with the size of less than or equal to 2000 nucleotides are formed from the stored precursors.

Animals↗
PubMedDate not supplied

[Molecular structure of pigeon genome. Revealing of clusters consisting of prolonged homopolymeric and short palindromic sequences].

Isolated from pigeon genome short (approximately 450 nucleotides) and long (approximately 8000 nucleotides) single-stranded DNA fragments containing prolonged (greater than or equal to 300 nucleotides) polydeoxyandenylic sequences have been studied. Based on the analysis carried out we come to the conclusion that for the pigeon genome the prolonged poly(dA)-sequences are located as clusters where a large amount of short palindromic sequences occur.

Animals↗
PubMedDate not supplied

[Reassociation of interspersed moderate DNA repeats].

Reassociation kinetics of the fragments of DNA consisting of interspersed repetitive and non-repetitive nucleotide sequences is considered in this paper. Based on the model, suggested by Gavrilov and Mazo (Mol. biol., 11, 101 1977), which takes into account the random DNA shearing, both reassociation kinetics of the total DNA in the region corresponding to interspersed repeat reassociation and that of the isolated preparation of interspersed repetitive sequences are calculated. In both cases influence of the repeat length on the reassociation rate is demonstrated. The estimation of the repetition frequency of rare repeats from pigeon genome is specified using calculations performed.

Animals↗
PubMedDate not supplied

[Globin-coding sequences in the nuclear 28S pre-mRNA and in the cytoplasmic RNA of pigeon erythroid cells].

The steady-state content of globin-coding sequences in nuclear and cytoplasmic RNA of pigeon erythroid cells was estimated by hybridization in the excess of nuclear 28S RNA and cytoplasmic poly(A) + RNA with [3H]DNA, synthesized on globin mRNA. Sequences of 9S globin mRNA are found in 0.06% of molecules of non-ribosomal 28S nuclear RNA (pre-mRNA) of erythroblasts and in 0.5% of molecules of non-ribosomal 28S nuclear RNA of reticulocytes. The content of globin mRNA in erythroblast cytoplasm is, respectively lower than in that of reticulocytes.

Animals↗
PubMedDate not supplied

[Isolation and characteristics of 2 transcribing families of pigeon-genome repetitive sequences].

From pigeon DNA two families of repeats have been isolated: one (frequency of repetitions 30--40 times per haploid genome) actively transcribing and the second (frequency of repetitions 2000--2800 times) weakly transcribing in erythroid cells. The reassociation kinetics, GC-content and size of isolated repeats were investigated. Actively transcribing repeats (average length of 350 nucleotides) contain about 55% GC-nucleotides and alternate in the genome with AT-rich sequences of the unique type. Comparison of isolated families of repeats revealed differences in the structure and posttranscriptional fate of RNA transcribed from them.

Animals↗
PubMedDate not supplied

Dimensions of homo- and heteropolymeric sections of DNA synthesized by reverse transcription from globin mRNA matrices.

The lengths of globin messenger RNAs, isolated from rabbit and pigeon reticulocytes, and single-stranded complementary DNAs, synthesized from mRNA in presence of RNA-directed DNA-polymerase and oligo(dt) have been investigated by polyacrylamide gel electrophoresis under denaturing conditions. The cDNA preparations contained a fraction which corresponded in length to the alpha and beta chains of the mRNA used as a matrix. The lengthwise distribution of poly(A) sequences, isolated from globin mRNAs, corresponded to a statistical distribution, with a maximum at 75-80 nucleotides and with a maximum length of approximately 150 nucleotides. The lengthwise distribution of poly(dt) sequences, isolated from cDNA, corresponded to the poly(A) sequence distribution. It was concluded that: 1) cDNA is heterogeneous with respect to the length of poly(dt) sequences located at the 5' end of the molecule; 2) there was no selective use as primer of only that oligo(dt) which was located within the complex formed with the 5' end of the mRNA poly(A) sequence; 3) the heterogeneity of poly(DT) corresponded qualitatively to two models of template-primer interaction: selective use as a true primer of the oligonucleotide located in the complex formed with the 3' end of mRNA, and a statistical distribution of primer along the poly(A) sequence; and 4) the heterogeneity of the homopolymeric section of the cDNA may affect the kinetics of hybridization with mRNA, which possibly explains the previously observed [1] anomalous dependence of the hybridization rate on time.

Animals↗
PubMedDate not supplied

[Primers for the nef gene in the diagnosis of HIV infection using the polymerase chain reaction].

A new system of primers and internal probe identifying the nef gene of HIV-1 was selected and tested for the laboratory diagnosis of HIV infection by means of PCR. The proposed primers and probe by their characteristics approached the optimal ones for PCR diagnosis. The diagnostic value of the above system was confirmed by the PCR analysis of blood samples from 29 patients including subjects with a doubtful diagnosis of HIV infection. The results of the PCR analysis using primers nef1/nef2 correlated with the results obtained by employing the widely used primers for the gag gene SK38/SK39 and attested to the high specificity and diagnostic efficiency of the proposed system.

Acquired Immunodeficiency Syndrome↗