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M K Malysheva

Publications and source records attributed to M K Malysheva.

At least 19 recordsLinked to original sources
PubMed1992

Latrotoxin-like properties of a protein from brain.

In bovine brain cortex cytoplasm we have identified a soluble protein (L-protein) of M(r) approximately 90 kDa interacting with polyclonal antibodies to alpha-latrotoxin. The L-protein forms potential-dependent and cation-selective ion channels in BLM, which are blocked by Cd2+. The fusogenic activity of the L-protein was demonstrated on liposomes. We have arrived at the conclusion that the action mechanisms of the L-protein and alpha-latrotoxin are similar.

Animals↗
PubMed1992

[Influence of phosphorylation on the functional properties of the sodium channel reconstructed in an artificial membrane].

Phosphorylation of the reconstructed TTX-sensitive cytosolic protein of the bovine brain has been studied. Some properties of the protein are similar to those of the membrane potential-dependent sodium channel. It is shown that the influence of phosphorylation by protein kinase A on the reconstructed channel greatly depends on the mode of reconstruction. Phosphorylation fo reconstructed channels in the open state leads to their closing. Preliminary phosphorylation of channel-forming protein results in a considerable increase of the activation effect of veratrine and scorpion toxin.

Animals↗
PubMed1991

[Polyamine modulation of phosphorylation of channel-forming cytosolic protein in bovine brain].

Phosphorylation of the bovine brain TTX-sensitive cytosolic protein which is similar in several functional properties to the membrane potential-dependent sodium channel has been studied. The results obtained indicate that the cytosolic protein is a substrate for cAMP-dependent phosphorylation. Polyamines at a concentration of 5.0 mmol/l inhibit markedly phosphorylation of the cytosolic protein. Spermine is shown to be the most effective inhibitor. It is suggested that polyamines may modulate the cell sodium channel function.

Animals↗
PubMed1990

Possible relationship of brain cytoplasmic tetrodotoxin-sensitive protein to voltage-gated sodium channel shown by monoclonal antibody.

Biochemical events leading to the formation of mature membrane-associated sodium channel proteins are not completely understood. We have recently purified a protein from the cytoplasm of brain cells, which is able to become incorporated into liposomes and induce neurotoxin-dependent sodium permeability. Here we report data on a monoclonal antibody derived against this protein. This antibody crossreacts with cell membrane preparations. The antibody binding to viable neuroblastoma cells is inhibited by veratrine, indicating that membrane molecules antigenically related to the cytoplasmic protein may also be related to the voltage-gated sodium channel.

Animals↗
PubMed1989

[Antigenic similarity of tetrodotoxin-sensitive cytoplasmic protein and nerve cell membrane proteins].

Reconstruction of membrane proteins obtained from the Sepharose-rabbit immunoglobulins to bovine brain TTX-sensitive cytoplasmic protein column has been studied. The detergent method for studying potential-dependent sodium channel has been used in our modification. The results obtained indicate that cytoplasmic TTX-sensitive proteins are close to those of the membrane sodium channel.

Animals↗
PubMed1987

[Purification of a soluble tetrodotoxin-sensitive protein from the cytoplasmic fraction of bovine brain tissue].

Highly purified protein inducing tetrodotoxin-dependent Na fluxes in liposomal membrane was obtained from the cytoplasmic fraction of the bovine brain. The protein was purified by anion-exchange chromatography on DEAE-Servacell and wheat germ agglutinin sepharose (WGA) followed by gel filtration on sepharose 4B. It is a high-molecular weight acidic glycoprotein; during denaturation under reducing conditions it forms 55 kD subunits. It is suggested that the tetrodotoxin-sensitive protein could be a soluble intracellular precursor of the voltage-dependent sodium channels.

Animals↗
PubMed1987

[Common features of the antigenic determinants presented on the membranes of mammalian nervous system cells and cytoplasmic tetrodotoxin-sensitive proteins].

Hypothetical antigenic similarities between nerve cell membrane structures and cytoplasmic tetrodotoxin-sensitive proteins have been studied. Indirect ELISA binding assay combined with inhibition assay has been used. The results obtained indicate that cytoplasmic tetrodotoxin-sensitive proteins do share antigenic determinants with nerve cell membrane structures. This is consistent with the speculation that cytoplasmic tetrodotoxin-sensitive proteins are relatives of membrane sodium channels.

Animals↗
PubMed1982

Tetrodotoxin-sensitive protein in the extracts from excitable tissues.

The sodium permeability of liposomes preincubated with the soluble fraction of brain and heart muscle homogenates was increased veratrine. The veratrine increment was decreased by tetrodotoxin. The effect was specific for the extracts from excitable tissues. Bovine serum and soluble fraction of liver homogenate induced neither veratrine- nor tetrodotoxin-sensitivity of the liposomes. Treatment of the excitable tissue extracts by pronase and heat denaturation caused their complete inactivation. Tetrodotoxin-sensitive factor could be fractionated by ammonium sulfate precipitation and by DEAE-Servacel chromatography. On a column of Sephadex G-200 it was eluted with the void volume. It is suggested that the tetrodotoxin-sensitive factor is a protein which could be a soluble precursor of the voltage-dependent sodium channels.

Animals↗
PubMed1981

[Detection of tetrodotoxin-sensitive structures in membrane and cytoplasmic fractions of Paralitodes camtschatica King crab nerve].

The membrane fraction isolated from the crab nerve was treated by ultrasonic irradiation to obtain closed osmotically active vesicles. The liposomes from brain lipids were modified by a cytoplasmic fraction to assay the tetrodotoxin influence on the 22Na influx into such liposomes. The 22Na influx into vesicles and modified liposomes was studied in the presence and absence of substances which change sodium conductance of excitable membranes. It is shown that tetrodotoxin at concentrations blocking electrical excitation in vivo decreased the sodium influx into membrane vesicles and modified liposomes.

Animals↗
PubMed1980

The association of tetrodotoxin-sensitive, sodium-selective ionophore of brain membranes with liposomes.

The tetrodotoxin-sensitive, sodsium-selective ionophore of nerve membranes has been associated with liposomes by adding the solubilized brain microsomal fraction to a cholate/phospholipid dispersion and subsequently removing the detergent from suspension by using gel chromatography. A stimulation of the efflux of sodium from the vesicles was observed in the presence of veratrine. Tetrodotoxin itself did not effect the sodium permeability, but inhibited the veratrine-induced increment. The activation was absent in the liposomes prepared without soluble membrane proteins. The effects demonstrated for tetrodotoxin and veratrine were specific for the Na+ movement. It was possible to precipitate the tetrodotoxin-sensitive ionophore by use of (NH4)2SO4.

Animals↗
PubMed1979

[Reconstruction of tetrodotoxin-dependent passive transport structures in liposomes].

Proteoliposomes were obtained from cholate solubilized components of membrane fraction and crude phospholipid fraction from the calf brain. Permeability of the proteoliposomes was studied using Na22 and Rb86 tracers. Veratrine was shown to activate and tetrodotoxin to inhibit Na22 efflux from proteoliposomes, while Rb86 efflux was not affected by the drugs used. These results demonstrate reconstitution of tetrodotoxin-dependent structure inducing selective sodium passive transport in artificial membranes.

Chemical Phenomena↗
PubMed1977

[Identification of sodium channels in vitro].

The membrane fraction isolated from cattle brain and vagal nerve was treated by ultrasonic irradiation in the presence of 22Na. It was shown that 22Na was trapped in vesicles formed from sonicated membranes in an osmotically active forms and slowly released into a nonradioactive solution. The efflux of 22Na from vesicles was studied in the presence and in the absence of substances which change the sodium conductance of excitable membranes. The local anesthetics (procaine, dibucaine) and tetrodotoxin at concentrations blocking electrical excitation in vivo decreased the sodium efflux from the vesicles. Veratrine, an activator of sodium channels, increased this efflux. The results are interpretated as an indication of the presence of functionally active sodium channels in the isolated membrane fragments.

Anesthetics, Local↗
PubMed1976

[Study of the interaction of Na+ and K+-ATPase of erythrocytes with ouabain. Effect of acetyl phosphate and p-nitrophenyl phosphate].

Effects of ATP, acetyl phosphate (AcP) and p-nitrophenyl phosphate (p-NPP) on the inhibition of the Na+, K+-ATPase activity were studied. ATP, AcP and p-NPP were found to facilitate the ouabain-induced inhibition of the enzyme activity only after the injection of these phosphorylyzing agents into the erythrocyte ghosts. Inside the ghosts Na+ ions enhanced the effects of the phosphorylyzing agents. K+ ions in the environment removed the stimulating effects of ATP, AcP and p-NPP on the ouabain-induced inhibition of Na+, K+-ATPase activity. It is concluded that the sites of AcP and p-NPP hydrolysis as well as the active center for ATP are localized on the inner surface of the cell membrane.

Adenosine Triphosphatases↗