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N D Ozerniuk

Publications and source records attributed to N D Ozerniuk.

At least 19 recordsLinked to original sources
PubMed1978

[Transfer of proteins synthesized in the cytoplasm into mitochondria. Stimulation of mitochondrial protein synthesis by microsomal fraction].

The in vitro transport into mitochondria of proteins synthesized in the cytoplasm was studied. The system, in which the microsomes synthesize protein in the presence of mitochondria directly during the experiment proved to be the most efficient one. The microsomal fraction significantly stimulated the incorporation of 14C-valine into the isolated mitochondria proteins. The effects of EDTA treatment of the mitochondrial fraction, the dependence of protein synthesis stimulation on the ratio of mitochondria and microsomal proteins and the kinetic pattern of the reaction suggest that the stimulation of the labelled precursor incorporation into mitochondrial proteins is not probably due to the labelled microsomes adsorption on the mitochondria.

Animals↗
PubMed1976

[Changes in mitochondria density during oogenesis of loach].

The growth of loach oocytes is accompanied by an increase in the density of mitochondria. Simultaneously with the increase in density an acceleration of 14C-valine incorporation into mitochondrial proteins takes place. It is assumed that the increase in mitochondria density during oogenesis is due to an increase in the amount of membrane material per unit of mitochondria weight.

Animals↗
PubMed1976

[Characteristics of synthesis of mitochondrial proteins during oogenesis in the loach].

The intensity of incorporation of a labelled precursor in the oocyte mitochondrial proteins in vivo increased at the early stages and decreased at the late stages of oogenesis in much the same way as the intensity of respiration and the concentration of mitochondria in oocytes. The intensity of incorporation of the labelled amino acid in the oocyte mitochondrial proteins in vitro suffered no changes during oogenesis.

Animals↗
PubMed1975

[Growth and reproduction of mitochondria in loach oocytes].

The size and number of mitochondria markedly increase at the early stages of oogenesis in the loach (Misgurnus fossilis). The growth of mitochondrial membranes in the oocytes is characterized by the contact with the rough endoplasmic reticulum. In the period of slow growth of oocytes, the number of mitochondria increases 82 times and by the beginning of vitellogenesis 240 times. Two fractions of mitochondria were noted in the early oocytes: dividing mitochondria localized in the perinuclear zone and non-dividing ones in the periphery of the oocyte. In the period of slow growth of oocytes, 1--2% of dumb-bell-like mitochondria were found. It was calculated that the doubling of the number of mitochondria in the early oocytes proceeded during 1.5 months.

Animals↗
PubMedDate not supplied

[Dynamics of the intensity of respiration in early embryogenesis of amphibians].

We studied growth and respiration rate during early ontogenesis of the axolotl Ambystoma mexicanum, Bosca's newt Triturus waltlii, the green toad Bufo viridis, and the smooth clawed frog Xenopus laevis. The respiration rate in these amphibian species increases during embryonal and larval development, peaks after transition to active feeding, and decreases at later stages of ontogenesis. The patterns of dynamics of this energy metabolism index in tailed and tailless amphibians have some differences related to their specific development. The changes in respiration rate in the embryos and larvae are correlated with the concentrations of mitochondria.

Amphibians↗
PubMedDate not supplied

[Constructive synergism of regulatory genes expressed in the course of the eye and muscle development and regeneration].

The expression patterns of regulatory genes involved in the formation of the eye in Drosophila and vertebrates during early development were analyzed comparatively. The results demonstrated that, although the compound eyes of invertebrates and the camera eyes of vertebrates markedly differ in their structure and development, they exhibit a striking similarity at the molecular level. This similarity manifests itself in the fact that the homologous regulatory genes ey/Pax, eya/Eya, dac/Dac, and so/Six, which control the early stages of eye development, are expressed in both groups. Not only was synergism shown in the expression of early regulatory genes, but direct interactions of ey/Pax- and so/Six-encoded transcription factors with DNA and protein-protein interactions between nuclear transcription factors encoded by eya/Eya and dac/Dac were also revealed. Transcription factors produced by expressing gene cascades--ey/eya/dac/so in invertebrates and Pax/Eya/Dac/Six in vertebrates--from the transcription complexes that control eye morphogenesis. Paradoxically, the development of muscles in vertebrates proved to involve the expression of genes homologous to the same regulatory genes that control eye morphogenesis in invertebrates and vertebrates. In the developing muscles, regulatory genes also produce transcription factors that form transcription complexes with the mechanism of action based on protein-DNA and protein-protein interactions. The processes of regeneration in the eye and skeletal muscles are controlled by the homologues of the same regulatory genes. Thus, the Pax/Eya/Dac/Six regulatory network is a general system involved in regeneration as well as in development.

Animals↗
PubMedDate not supplied

[Different functional and structural properties of lactate dehydrogenase isozymes at different stages of Danio rerio ontogenesis].

We studied properties of lactate dehydrogenase isozymes expressed at different stages of Danio rerio ontogenesis. H4-LDH and a minor fraction H3M1 are expressed during embryonic development. The muscle isozyme (M4) appears after the beginning of muscle contractions in the embryo. H4 and M4 isozymes isolated from the heart and skeletal muscle of the adult fish, respectively, show significant differences in terms of Km, activation energy (AE), and inactivation temperature. H4-LDH isozymes isolated from unfertilized eggs, the skeletal muscle of larvae, and the heart of the adult fish differ in Km and activation energy, as well as in inactivation temperature. We propose that these differences may be associated with a ligand interacting with the H4 isozyme at different steps of ontogenesis.

Animals↗
PubMedDate not supplied

[Development of the gill system in early ontogenesis of Danio and nine spike stickleback].

We studied specific features of development of the gill system during ontogenesis of the zebrafish Danio rerio and ninespine stickleback Pungitius pungitius, which differ in the rates of gill system, development. Although the development of sticklebacks proceeds in nature at lower temperatures than for zebrafish, the rate of gill formation in the former is higher. These differences are related to the specific conditions in which these fish develop: embryonic and larval development of the stickleback proceeds in bodies of water with a lower oxygen content than for zebrafish, and this results in the adaptive alteration of the rate of gill system development. Differentiation of gills in the zebrafish is accompanied by a manifold increase in the oxygen consumption rate. At different developmental stages, the incremental rates of oxygen consumption and increase in the body mass of the zebrafish larvae and fry differed significantly.

Animals↗
PubMedDate not supplied

[Effect of thermal acclimation on the expression of gene coding for lactate dehydrogenase A4 in loach skeletal muscle].

Acclimation of Misgurnus fossilis to 5 and 18 degrees C induced considerable changes in LDH-A gene expression in white skeletal muscle. Qualities of total and messenger RNA isolated from weighted portions of muscle are considerably higher after acclimation to 18 degrees C as compared to 5 degrees C. However, a PCR assay of cDNA synthesized from these mRNA and equalized by optical density demonstrated that the level of LDH-A gene expression was indistinguishable for high and low acclimation temperatures, while expression of other genes (glyceraldehyde-3-phosphate dehydrogenase and alpha-actin) considerably increased at 18 degrees C as compared to 5 degrees C. The specific enzymatic activity of LDH from white skeletal muscle of the fish acclimated to low temperature is by 20% higher than that for high-temperature acclimation. Structural analysis of the PCR products synthesized on cDNA-5 degrees C and cDNA-18 degrees C has revealed no differences. However, there are indirect indications of the differences in the C-thermal region of the LDH-A molecule. Northern hybridization reveals the differences at the RNA level: one (1400 bp) or two (about 1600 and 1400 bp) hybridization signals have been found in mRNA-5 degrees C and mRNA-18 degrees C, respectively. The presence of two fractions in the mRNA-18 degrees C indicates alternative splicing.

Adaptation, Physiological↗