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The involvement of active oxygen forms in the regulation of the expression of mitochondrial respiratory chain components, which are not related to energy storing, has been in vitro and in vivo studied in Lycopersicum esculentum L. The highest level of transcription of genes encoding alternative oxidase and NADH dehydrogenase has been observed in green tomato leaves. It has been shown that even low H2O2 concentrations activate both aoxlalpha and ndb1 genes, encoding alternative oxidase and external mitochondrial rotenone-insensitive NADH dehydrogenase, respectively. According to our results, in the case of an oxidative stress, alternative oxidase and NADH dehydrogenase are coexpressed in tomato plant tissues, and active oxygen forms serve as the secondary messengers of their coexpression.

Cell respiratory activity of protoplasts obtained from the wild type of Neurospora crassa and photoreceptor complex WCC--white collar 1 (wc-1) and white collar 2 (wc-2)--mutants of Neurospora crassa strains was investigated. Respiration inhibition by KCN in the presence of 25 mM succinate was similar in all strains and did not exceed 83-85% against control. The significant induction of KCN-resistant respiratory pathway occurred under 1% glucose oxidation in wc-1 and wc-2 mutants if compared with the wild type strains. The inhibitors of the main (cytochrome) pathway of electron transfer in mitochondria-1 mM KCN and antimycin A (4 microg/ml)--blocked the respiration rate of the protoplasts from N. crassa wild type by 75%, while the cell respiration of wc-1 and wc-2 strains was suppressed by approximately 50%. The specific inhibitor of alternative oxidase--10 mM salicylhydroxamic acid (SHAM)-in combination with the blockers of mitochondrial electron transfer chain caused the total suppression of respiratory activity of protoplasts in all studied strains. It is supposed that an increase of KCN-resistance in WCC mutants under glucose oxidation is connected with alternative oxidase activation as the result of failure in reception and signal transduction of active oxygen species.

The aim of this study was the search of association of polymorphic markers T(-365)C of POLG1 gene, G(-25)A of ANT1 gene and G(-605)T of PEO1 gene with diabetic polyneuropathy (DPN) in type 1 diabetes mellitus (T1DM) patients. All patients were ethnic Russians from Moscow, with a T1DM record of no more than 5 years and DPN or a T1DM record of more than 10 years but without DPN. We have found that polymorphic marker T(-365)C of POLG1 gene was associated with DPN in Russian patients with T1DM. The carriers of C allele and CC genotype had higher risk of DPN development (OR = 1.62; CI = 1.11-238; and OR = 1.76; CI = 0.99-3.13; relatively). On the contrary, the carriage of T allele and TT genotype were associated with the lower risk of DPN development (OR = 0.62, CI = 0.42-0.90; and OR = 0.61; CI = 035-1.07; relatively). We have not found any association of polymorphic markers G(-25)A of ANT1 gene and G(-605)T of PEO1 gene with DPN in Russian patients with T1DM living in Moscow.

Heat shock (45 degrees C) and the effect of oxidants (H2O2) resulted in a decrease of the respiratory activity of yeast cells and their survival rate. Increased resistance to stress effects after mild heat treatment (37 degrees C) or treatment with a nonlethal dose of oxidants (0.5 mM H2O2 for 60 min) was accompanied by appearance of an alternative (cyanide-resistant) oxidative pathway in the mitochondria, which promotes survival due to retention of the capacity for ATP synthesis in the first coupling point at the level of endogenous NADH dehydrogenase. The alternative oxidative pathway is more resistant to the effect of stressors that disrupt electron transfer in the cytochrome site of the respiratory chain.

A 147-bp cDNA fragment was isolated from human lymphocytes activated with concanavalin A using the method of direct selection. A complete copy of the selected gene having total homology with the mitochondrial ribosomal gene MRPL37 was obtained by the RACE (rapid amplification of cDNA ends) technique. The MRPL37 gene was localized on human chromosome 1 using a DNA panel composed of somatic cellular human-hamster hybrids. The Northern blotting and RT-PCR (reverse transcription-polymerase chain reaction) demonstrated that the RNA of the human MRPL37 gene is widely represented in the lymphoma populations of Raji B cells and MT4 T cells, as well as in pancreas, liver, and lung embryonic fibroblasts WI-38 and LEH. The highest expression level of the MRPL37 mouse homologue was found in the cells of skeletal muscles, the heart, and organs of reproductive system: the uterus, ovaries, and testicles. A comparative analysis of the MRPL37 amino acid sequence with those of proteins represented in the Fasta33 and GenBank databases showed a homologous region in MRPL37 and PDCD9 (programmed cell death 9, MPRS30) proteins. The chicken homologue of PDCD9 is interesting because its overexpression causes apoptosis of the mouse fibroblasts C3H10T1/2. The existence of a common domain indicates possible similar functional peculiarities of the PDCD9 and MRPL37 genes and may imply the MRPL37 involvement in the process of apoptosis. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 5; see also http: // www.maik.ru.

The study of the effect of nucleoside phosphates on the activity of cyanide-resistant oxidase in the mitochondria and the submitochondrial particles of Yarrowia lipolytica showed that adenosine monophosphate (5'-AMP, AMP) did not stimulate the respiration of the intact mitochondria. The incubation of the mitochondria at room temperature (25 degrees C) for 3-5 h or their treatment with ultrasound, phospholipase A, and detergent Triton X-100 at a low temperature inactivated the cyanide-resistant alternative oxidase. The inactivated alternative oxidase could be reactivated by AMP. The reactivating effect of AMP was enhanced by azolectin. Some other nucleoside phosphates also showed reactivating ability in the following descending order. AMP = GMP > GDP > GTP > XMP > IMP. The apparent reaction rate constant Km for AMP upon the reactivation of the alternative oxidase of mitochondria treated with Triton X-100 or incubated at 25 degrees C was 12.5 and 20 microM, respectively. The Km for AMP upon the reactivation of the alternative oxidase of submitochondrial particles was 15 microM. During the incubation of yeast cells under conditions promoting the development of alternative oxidase, the content of adenine nucleotides (AMP, ADP, and ATP) in the cells and their respiration tended to decrease. The subsequent addition of cyanide to the cells activated their respiration, diminished the intracellular content of ATP three times, and augmented the content of AMP five times. These data suggest that the stimulation of cell respiration by cyanide may be due to the activation of alternative oxidase by AMP.

In order to determine the role of the plasma membrane H(+)-ATPase and alternative oxidase (alternative pathway of respiration) in the regulation of intracellular pH during development of the tobacco male gametophyte, we studied the changes in pH due to the inhibition of these enzymes by orthovadanate and benzhydroxamic acid, respectively. The inhibition of these enzymes decreased the intracellular pH at all three studied stages of the male gametophyte development: middle and late binuclear pollen grains and activated mature pollen grain. The data obtained suggest that H(+)-ATPase and alternative oxidase are involved in the regulation of intracellular pH of the pollen grain during its differentiation and activation that precede germination. At the same time, during the recovery of intracellular pH after its acidification by propionic acid, it was found that other mechanisms, not related to the above mentioned, greatly contribute to the regulation of pH.

Brown adipose tissue (BAT) is universally present in mammals. Thermal production in such tissue is physiologically important for maintaining temperature homeostasis and regulation of body mass in small-size homoiotherms. At present it is clearly established that unlike other large mammals, brown adipose in man and primates is retained throughout the whole postnatal othogenesis. Therefore, BAT appears as a possible effector of pharmacogenetic protection from human excessive adiposis. Systematic reserach of various functioning aspects of this unique organ of mammals were started abroad as early as 1960-es, and are actively developing at present. Domestic research of energy circulation physiology and of thermoregulation developed mostly outside the brown adipose tissue. Therefore, the principal objective of this publication is to draw attention of experimental and clinical researches to an intriguing aspect of the issue of energy circulation in humans--the issue of brown adipose functioning.

The pretreatment of Saccharomyces cerevisiae and Debaryomyces vanriji with sodium azide was found to induce thermotolerance in both yeasts, whereas sodium azide used in combination with heat shock enhanced the thermotolerance of S. cerevisiae and substantially decreased the thermotolerance of D. vanriji. It is suggested that the different responses of the yeasts to sodium azide during heat shock are due to the different functional organizations of their mitochondrial apparatus.

The effect of cyanide, antimycin A, ethanol, and acetate on the induction of alternative oxidase in the yeast Yarrowia lipolytica VKM Y-155 sensitive to cyanide, in the presence of the aforementioned compounds led to the development of cyanide-resistant respiration, which could be suppressed by benzohydroxamic acid, an inhibitor of alternative oxidases. The incubation of cells with cyanide, ethanol, or acetate raised the intracellular pool of cAMP, which attained maximal values after a 2- to 3-min incubation, then rapidly decreased to the initial value and did not change over the next three hours of incubation. The possible role of cAMP in the induction of alternative oxidase in yeast cells is discussed.

Effect of an ADP/ATP antiporter inhibitor carboxyatractylate on permeability of inner mitochondrial membrane was studied. Carboxyatractylate induced two uncoupling systems: Ca(2+)-dependent pore and another system which was sensitive to an inhibitor of calcium uniporter ruthenium red (apparently, Ca(2+)-recycle). Extent of Ca(2+)-recycle induction correlates with a fraction of mitochondrial population which underwent permeabilization; inhibition of permeabilization by cyclosporin A prevents induction of the recycle. Thus, induction of Ca(2+)-dependent pore is direct consequence of carboxyatractylate binding to mitochondria whereas induction of Ca(2+)-recycle is indirect. Both uncoupling systems are induced by carboxyatractylate concentrations which are specific for ADP/ATP antiporter. The data suggest that the antiporter can directly participate in the formation of Ca(2+)-dependent pore in inner mitochondrial membrane.

It has been found that inhibition of mitochondrial ATPase in living thymocytes and Ehrlich ascites carcinoma (EAC) cells after incubation of cells with uncoupler, rotenone or cumene hydroperoxide, depends, in a large measure, on the inhibitor protein (IF1) action. Maximum inhibition (up to 70% of the oligomycin-sensitive ATPase activity) was found in the presence of the uncoupler in the incubation medium. Even when IF1 action was maximum, the residual ATPase activity caused marked ATP depletion in thymocytes, while in EAC cells other ATP-consuming processes prevailed. No inactive ATPase-IF1 complexes were found in intact thymocytes and EAC cells. The extent of inhibition of mitochondrial ATPase under oxidative stress was higher in thymocytes than in EAC cells and depended on cumene hydroperoxide concentration and duration of cell cellular ATP depletion. It is suggested that under certain experimental conditions IF1 can prevent cell death by slowing down the hydrolysis of cellular ATP.

Cytoplasmatic glycoprotein previously shown to be an inhibitor of mitochondrial membrane permeability for oxidation substrates inhibits in-vitro gluconeogenesis from pyruvate, lactate, succinate, alpha-ketoglutarate and glutamate in slices of the renal cortical layer. The inhibition was reduced with Ca2+ concentration increase in the incubation medium from 0.02 to 2 mM.

Upon starving and muscle work the activity of an insulin-dependent cytoplasmic regulator (IDR) in the rat liver has been demonstrated to be lowered. This is one of the mechanisms of glycogenolysis and gluconeogenesis stimulation. Rapid increase in IDR activity in the heart and liver has been recorded in the period of recovery after swimming, with the increase being more intense in the heart. It has been shown that in the heart the resynthesis of glycogen proceeds more rapidly than in the liver. Therefore, the rate of glycogen resynthesis by the liver and heart correlates with IDR activity.

The study was aimed to examine properties of polyclonal antibodies elicited after immunization by cytoplasmic nerve cell glycoproteins forming sodium channels in liposomes. It was shown that intact murine neuroblastoma cells can absorb these antibodies. Absorbing cell dose-effect curves were found to have a characteristic form able to shift when the cell culture time or serum concentration in the growth medium varied.

Isolated from brown adipose tissue mitochondria of newborn guinea pigs thermogenin forms ion channels in BLM which are analogous with mitochondrial porin channels.

During thyroidectomy, the stimulating action of the catalytic amounts of a thermostable fraction of rat liver and diaphragm cytoplasm on Ca2+ transport in mitochondria, which indicates the decrease of the activity of an insulin-dependent cytoplasmic regulator (IDR) in insulin target organs. Thyroidectomized rats also manifested a decrease in blood insulin and glucose concentrations. Administration of the physiological doses of thyroxine produced an increase in both blood glucose concentration and IDR activity in the liver and diaphragm of thyroidectomized rats. Experiments with measuring the kinetics of the swelling of deenergized mitochondria in isoosmotic solution of ammonium pyruvate demonstrated the inhibition of liver mitochondrial swelling in thyroidectomized rats.

The activity of the insulin-dependent regulator (IDR) in the thermostable fraction of the cytoplasm isolated from the liver, heart and diaphragm of rats as well as the glycogen level in the liver were estimated. The IDR activity in the insulin target organs and glycogen concentration in the liver were raised in the pregnant well-fed rats; a tendency to their decrease was observed after 24 h starvation. The range of changes between satiation and starvation was much more pronounced in the pregnant rats than in the controls. The IDR activity was also higher in well-fed rats receiving progesterone for 5 days and did not change after a single injection of progesterone. It was concluded that a raised level of progesterone in the blood was one of the reasons for an increase in the IDR activity in pregnant rats. An increase in the IDR activity in the insulin target organs under conditions of insulin resistance induced by pregnancy or progesterone administration testifies to the fact that the binding of insulin with its receptors is not a limiting link in the mechanism of insulin action.