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V Z Tarantul

Publications and source records attributed to V Z Tarantul.

At least 55 records · Page 3Linked to original sources
PubMed1978

[Molecular organization and genome expression in eukaryotes].

The recent data on the structural organization and expression of genome in eukaryotes are reviewed. Different types of nucleotide sequences (repetitions, palindromes, homopolymers) represented in the regions of genome transcription, as well as in mRNA's of the cytoplasm and nuclear messenger-like RNA's are analyzed. Probable functions of different types of sequences are discussed. The problem of nuclear precursors of cytoplasmic mRNA's and in particular heterogeneous nuclear RNA is considered. It is noted that this population of molecules is heterogeneous not only by the molecular weight, but also by some other parameters. Stable messenger-like 28S and 18S RNA's found in the nuclei are described. In addition to the already known scheme of rapid posttranscriptional processing of pre-mRNA, a hypothesis is put forward to the effect that the selective transport of mRNA molecules stored in the nucleus from the nucleus into the cytoplasm is realized at the expense of extended processing.

Animals↗
PubMed1978

[Structure of the mRNA of eukaryotic cells].

A review is given of the principal achievements in studying the structure of mRNA in eukaryotic cells. The data are provided on the size and life time, complexity and distribution of different kinds of mRNA by the frequency of repetitions; composition and structure of mRNP. The structures of individual mRNA's and general pattern of the structure of eukaryotic mRNA and mRNP are considered.

Animals↗
PubMed1977

Purification and characterization of two transcribed repetitive DNA fractions from the pigeon genome.

Two fractions of the repeats belonging to intermediate frequency repetitive DNA were isolated from the total pigeon nuclear DNA fragmented to about 450 nucleotides. One fraction was designated as "rare repeats" (repetition frequency about 35 per haploid genome) and another termed as "moderate repeats" (repetition frequency about 2500 per haploid genome). The rare repeats, which constitute about 7% of the total DNA, include at least 75% of the repetitive DNA sequences transcribed into the high molecular fraction (greater than 45S) of HnRNA in erythroid cells. These repeats have properties compatible with the characteristics of the class of low frequency interspersed DNA found in genomes of many other Metazoan species. The moderate repeats contribute only about 10-20% of the total repetitive DNA copies present in greater than 45S HnRNA and differ from the rare repeats in some other properties.--The possible role of the rare repeats in the genome is discussed.

Animals↗
PubMed1975

Hybridization of pigeon globin messenger RNA with complementary DNA synthesized in vitro by reverse transcription: influence of the homopolymeric regions.

The kinetics of hybridization of pigeon globin messenger RNA with complementary cDNA synthesized by means of AMV reverse transcriptase is complex. Addition of poly A or poly U in excess to the reaction mixture normalized the kinetics. It is concluded that association of the complementary homopolymeric regions of mRNA and cDNA accelerates the complex formation between heteropolymeric sequences in a fraction of the molecules.

Adenine Nucleotides↗
PubMed1975

Influence of ecdysterone on the growth of cells and synthesis of macromolecules in established cell lines of Drosophila melanogaster.

Ecdysterone (beta-ecdysone) and 2-deoxy-alpha-ecdysone specifically inhibit the growth of established embryonic cells of D. melanogaster. A preparation of alpha-ecdysone is 100 times less active than ecdysterone. The action of ecdysterone is eliminated when it is removed within 24 h, but after 48 h the inhibiting influence of the hormone becomes irreversible. The diploid line, triploid and tetraploid sublines are sensitive to ecdysterone. The diploid subline with a spontaneously arisen translocation of an X-chromosome to an autosome of the third pair is substantially more resistant to ecdysterone. At 24 h after the addition of ecdysterone, there is a 2-5-fold suppression of the synthesis of total RNA; DNA synthesis is lowered to the same degree only after 48 h. The gross synthesis of proteins, measured according to the incorporation of C 14-lysine, was not suppressed even after 48 h.

Animals↗