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V I Tiulenev

Publications and source records attributed to V I Tiulenev.

At least 19 recordsLinked to original sources
PubMed1993

[ATP-dependent structural changes in chromatin].

Incubation (1 hour, 37 degrees C) of nuclei and chromatin from guinea pig spleen (but not from thymus or the liver) resulted in a proteolysis of H1 and H2A histones and accumulation of specific hydrolytic products. Sodium dodecyl sulfate gel electrophoresis revealed a decline in H1 and H2A and the appearance of new protein bands under histone H10 and between H2A and H4. ATP (10 mM) (but not cAMP or PPi) added to the incubation mixture prevented the H1 and H2A digestion and accumulation of the aforementioned products. The ATP, which protects the histones in the nucleus and chromatin from proteinases, promoted the cleavage of cytosolic low molecular weight proteins. The mechanisms of ATP-dependent chromatin structural rearrangements determining the resistance of nuclear proteins to proteolysis are discussed.

Adenosine Triphosphate↗
PubMed1991

[A rapid method of preparing the (H3-H4-H2A-H2b)(2) histone octamer in large quantities].

A simple and fast method for isolation of large amounts of the histone octamer (H2A-H2B-H3-H4)2 is proposed. This method is based on chromatin adsorption by hydroxyapatite with subsequent extraction of the histone octamer with 50 mM sodium-phosphate buffer containing 4 M NaCl pH 8.0. It was shown that the properties of the histone octamer isolated by this extractive procedure are identical with those of the histone octamer obtained by elution on a Sephadex G-100 column. The histone tetramer (H3-H4)2 and dimer (H2A-H2B) were obtained after gel filtration on Sephadex G-100 in 50 mM sodium-acetate (pH 5.6).

Animals↗
PubMed1984

[Effect of neuromediating and neuroblockading hormones on the RNA synthesis in the rat liver nucleus].

It was shown that rRNA and HnRNA synthesis in rat liver nuclei does not change-within 30 min after intraperitoneal injection of acetylcholine (0.005 mg per 100 g of body weight) but decreases after injection of norepinephrine and epinephrine (0.05 mg per 100 g of body weight). The synthesis of rRNA (but not of HnRNA) increases after injection of hydrocortisone (2,5 mg per 100 g of body weight). The synthesis of HnRNA (but not of rRNA) increases after injection of ACTH1-24 (3 ME per 100 g of body weight) and oxytocin (1 ME per 100 g of body weight). The synthesis of rRNA decreases after injection of propranolol and atropine (0.5 mg per 100 g of body weight). At the same time, the synthesis of HnRNA does not change thereby. The inhibitory effect of propranolol and atropine was corrected by electrostimulation of hypothalamus. The content of cAMP and Ca2+ and the phosphorylation degree of nuclear proteins are increased after stimulation of hypothalamus. The phosphorylation of nuclear proteins is increased by 10(-8)-10(-6) M cAMP. The synthesis of RNA in liver nuclei is increased by 10(-6) M cAMP only after addition of cytosol. In this case the activity of RNA-polymerase II increases in a greater degree than that of RNA-polymerase I + III. It is assumed that the regulatory mechanisms of rRNA and HnRNA synthesis are different. The role of hypothalamus electrostimulation, neurotransmitters, hormones, and cAMP in the mechanisms of RNA synthesis in rat liver nuclei is discussed.

Acetylcholine↗
PubMed1983

[Effect of protein S-100 on phosphorylation of nuclear proteins of cells of rat brain and liver].

The effect of acidic neurospecific protein S-100 on the phosphorylation of brain and liver nuclear proteins with 1 and 10 microM ATP was investigated. It was shown that protein S-100 increases the phosphorylation of brain nuclear proteins, while antigen D, another acidic neurospecific protein half-identical to 14-3-2 protein, inhibits this process. Ca2+ and cAMP at concentration of 10(-6) M do not affect the phosphorylation of brain nuclear proteins. In control assays the tracer 32P is presumably incorporated into high molecular weight nuclear protein fractions (Mr greater than 40000). After addition of protein S-100 the tracer is mainly incorporated into these proteins as well independently of ATP concentration (1 or 10 microM). The phosphorylation of nuclear proteins with molecular weights above 100000 is mostly increased in this case. At ATP concentration of 1 microM protein S-100 decreases histone phosphorylation 2.3 times but does not affect that of non-histone proteins. However, at 10 microM ATP the inhibitory action of this protein on histone phosphorylation is absent. The possible mechanisms of protein S-100 action on nuclear proteins phosphorylation are discussed.

Animals↗
PubMed1980

[Turnover of chromatin proteins in rat liver during induction of RNA synthesis by electrostimulation of the hypothalamus].

It has been shown that the induction of D-RNA synthesis in rat liver nuclei by electrostimulation of hypothalamus is accompanied by a decrease in chromatin protein synthesis and an increase in phosphorylation and acetylation of chromatin proteins. The decrease of the histone synthesis is mainly due to the decrease of [14C]lysine and [14C]alanine incorporation into histones H1 and H4. The relationship between H1, H2b-H3, H2a and H4 histone fractions remains unchanged. Electrostimulation of hypothalamus increases acetylation of H2a and H4 histone fractions and phosphorylation of all histones with the exception of histone H1.

Acetylation↗
PubMed1976

[Aggregation of histone F2b inthe presence of salt and methanol].

The kinetics of histone F2b aggregation in the presenceof NaCl and methanole was investigated. The size of aggregates increases during 20 hours, and in the following 13 hours the size of formed complexes does not change. It was shown that the stable colloid system was formed by the olygomers of histone F2b.

Histones↗
PubMedDate not supplied

[The nervous system and the genetic apparatus of cells].

Electric stimulation of paraventricular hypothalamic nucleus results in intensification of RNA synthesis in rat brain. Content of acid proteins and RNA in liver and brain chromatin of geese changes in the period of sexual activity controlled by hypothalamus. With long introduction of hydrocortisone content of non-histone proteins of chromatine and RNA as well as total content of RNA in rat liver cells increases. These and other facts confirm the supposition that the central nervous system has an influence on the function of organs and tissues by means of genetical apparatus of cells.

Animals↗
PubMedDate not supplied

[Tertiary structure of histones].

Optical absorption and fluorescence of histones F2a and F2b were studied. An increase in pH and ionic strength induced the structure change in these histones fractions. The hydrofobic sites are formed in protein molecules and this leads to an intensification of histone-histone interactions. The change in the histone tertiary structure is of importance for processes associated with regulation of gene activity in eukaryotic cells.

Histones↗