During the process of intra-uterine mammalian fetal development, the oxygen supply in growing fetus is low. A rapid switch from glycolysis-based metabolism to oxidative phosphorylation (OXPHOS) must proceed during early postnatal adaptation to extra-uterine conditions. Mitochondrial biogenesis and mammalian mitochondrial F(o)F(1)-ATP synthase assembly (complex V, EC 3.6.3.14, ATPase) are complex processes regulated by multiple transcription regulators and assembly factors. Using RNA expression analysis of rat liver and skeletal tissue (Rattus norvegicus, Berkenhout, 1769), we describe the expression profiles of 20 genes involved in mitochondrial maturation and ATP synthase biogenesis in detail between the 16th and 22nd day of gestation and the first 4 days of life. We observed that the most important expression shift occurred in the liver between the 20th and 22nd day of gestation, indicating that the fetus prepares for birth about two days before parturition. The detailed mechanism regulating the perinatal adaptation process is not yet known. Deeper insights in perinatal physiological development will help to assess mitochondrial dysfunction in the broader context of cell metabolism in preterm newborns or neonates with poor adaptation to extra-uterine life.
- MeSH
- biogeneze organel MeSH
- fyziologická adaptace * MeSH
- játra embryologie růst a vývoj metabolismus MeSH
- novorozená zvířata růst a vývoj metabolismus MeSH
- pilotní projekty MeSH
- potkani Wistar MeSH
- protonové ATPasy biosyntéza MeSH
- stanovení celkové genové exprese MeSH
- svaly embryologie metabolismus MeSH
- těhotenství MeSH
- vývoj svalů MeSH
- zvířata MeSH
- Check Tag
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Názvy látek
- protonové ATPasy MeSH
A spontaneous mutant of Methanothermobacter thermautotrophicus resistant toward the ATP-synthase inhibitor N,N'-dicyclohexylcarbodiimide (DCCD) was isolated. DCCD normally inhibits methanogenic electron-transport-driven ATP synthesis, however, the DCCD-resistant strain exhibited methanogenesis in the presence of 300 micromol/L DCCD. Total ATP synthesis was shown to be higher in the mutant strain, both in the presence and absence of DCCD. These results suggested a modification in the ATP-synthesizing system of the mutant strain. Using Blue Native PAGE combined with MALDI TOF/TOF mass spectrometry, increased concentrations of both the A(1) and A(o) subcomplexes of the A(1)A(o)-type synthase were identified in the mutant strain. However, no alterations were found in the structural genes (atp) for the A(1)A(o) ATP synthase. The results imply that DCCD resistance is a consequence of increased A(1)A(o) ATP synthase expression, and suggest that genes involved in regulating synthase expression are responsible for DCCD resistance.
- MeSH
- adenosintrifosfát metabolismus MeSH
- archeální proteiny biosyntéza MeSH
- dicyklohexylkarbodiimid toxicita MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- exprese genu MeSH
- inhibitory enzymů toxicita MeSH
- léková rezistence * MeSH
- methan metabolismus MeSH
- Methanobacteriaceae chemie účinky léků izolace a purifikace metabolismus MeSH
- mutace * MeSH
- oxidace-redukce MeSH
- protonové ATPasy biosyntéza MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- upregulace MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- adenosintrifosfát MeSH
- archeální proteiny MeSH
- dicyklohexylkarbodiimid MeSH
- inhibitory enzymů MeSH
- methan MeSH
- protonové ATPasy MeSH
A low content of mitochondrial ATPase in brown adipose tissue (BAT) has previously been found to contrast with high levels of the transcripts of the beta-subunit of the F1 part of the ATPase and of the transcripts of the mitochondrial encoded subunits (Houstĕk, J., Tvrdík, P., Pavelka, S., and Baudysová, M. (1991) FEBS Lett. 294, 191-194). To delineate which subunit limits the synthesis of the ATPase complex, we have studied the expression of the nuclear genes encoding subunits alpha, beta, and gamma of the catalytic F1 part and the b, c, d, and OSCP subunits of the F0 part of the ATPase. In comparison with other tissues of mice, high levels of transcripts of alpha-F1, beta-F1, gamma-F1, b-F0, d-Fo, and OSCP were found in BAT. The only genes expressed at a low level in BAT were those of the c-F0 subunit. The levels of c-F0 transcripts were 4-70-fold lower in BAT than in other tissues. An analogous expression pattern of the ATPase genes was found in BAT of adult rat and hamster. In BAT of newborn lamb, which, in contrast to other mammals, has a high content of mitochondrial ATPase, correspondingly high levels of c-F0 mRNA were found Expression of the c-F0 genes also correlated well with the ontogenic development of BAT in the hamster, being high during the first postnatal week when mitochondria are nonthermogenic and contain a relatively high amount of ATPase, but low on subsequent days when ATPase content decreases, as the thermogenic function develops. It is suggested that expression of the c-F0 genes and subsequent synthesis of the hydrophobic subunit c of the membrane-intrinsic F0 part of the enzyme may control the biosynthesis of the ATPase complex in BAT. An analogous regulatory role of the c-F0 subunit could be postulated in other tissues.
- MeSH
- DNA sondy MeSH
- hnědá tuková tkáň enzymologie růst a vývoj MeSH
- inbrední kmeny myší MeSH
- jaterní mitochondrie enzymologie MeSH
- kosterní svaly enzymologie MeSH
- křečci praví MeSH
- křeček rodu Mesocricetus MeSH
- makromolekulární látky MeSH
- messenger RNA analýza biosyntéza MeSH
- mitochondrie enzymologie MeSH
- mozek enzymologie MeSH
- myši MeSH
- northern blotting MeSH
- novorozená zvířata MeSH
- orgánová specificita MeSH
- ovce MeSH
- protonové ATPasy biosyntéza MeSH
- regulace genové exprese enzymů * MeSH
- srdeční mitochondrie enzymologie MeSH
- stárnutí metabolismus MeSH
- tuková tkáň enzymologie MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA sondy MeSH
- makromolekulární látky MeSH
- messenger RNA MeSH
- protonové ATPasy MeSH
Brown adipose tissue (BAT) is the major thermogenic organ of the human neonate. To determine whether it is also active in the peripheral conversion of T4 to T3, as shown in several animal species, interscapular BAT from 13 newborns of 25-40 weeks gestational age who survived 4 days, at most, was investigated. BAT was found to contain significant amounts of the mitochondrial uncoupling protein (UCP), the rate-limiting component of heat production. The specific content of UCP increased from 29.4 +/- 3.3 to 62.5 +/- 10.2 pmol/mg protein between 25 and 40 weeks of gestation, respectively, and the UCP/F1-ATPase molar ratio, a sensitive marker of brown fat differentiation, increased similarly. BAT was also found to contain iodothyronine 5'-deiodinase (5'D), which appears to be a type II enzyme, based on high affinity for T4 (Km, 2.9 nmol/L) and insensitivity to propylthiouracil (10% inhibition by 1 nmol/L). 5'D was active by 25 weeks gestation, and the specific activity increased from 116 +/- 15 to 417 +/- 46 fmol/h.mg protein during the period examined. The development of 5'D activity was similar to the changes in UCP content; both exhibited a major increase before 32 weeks gestation. The results indicate that thermogenic function and 5'D activity develop in human BAT rather early, during the first half of the last trimester of gestation. The activities of 5'D in human BAT are comparable with 5'D activities found in animal BAT stimulated during the perinatal period, by cold exposure, or by increased cAMP levels.
- MeSH
- analýza rozptylu MeSH
- gestační stáří MeSH
- hnědá tuková tkáň metabolismus ultrastruktura MeSH
- imunoblotting MeSH
- iontové kanály MeSH
- jodidperoxidasa biosyntéza MeSH
- křečci praví MeSH
- křeček rodu Mesocricetus MeSH
- lidé MeSH
- membránové proteiny biosyntéza MeSH
- mitochondriální proteiny MeSH
- mitochondrie metabolismus MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- novorozenec metabolismus MeSH
- protonové ATPasy biosyntéza MeSH
- respirační komplex IV biosyntéza MeSH
- termoregulace MeSH
- transportní proteiny biosyntéza MeSH
- uncoupling protein 1 MeSH
- věkové faktory MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- novorozenec metabolismus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- iontové kanály MeSH
- jodidperoxidasa MeSH
- membránové proteiny MeSH
- mitochondriální proteiny MeSH
- protonové ATPasy MeSH
- respirační komplex IV MeSH
- transportní proteiny MeSH
- uncoupling protein 1 MeSH
Cells from a rapidly growing rat Zajdela hepatoma were shown to contain (on a protein basis) five-times less mitochondria than hepatocytes from resting or regenerating rat liver. Transcripts of four nuclear genes for representative mitochondrial membrane proteins (beta-F1 subunit and N,N'-dicyclohexyl-carbodiimide-binding protein of ATP synthase, subunit IV of cytochrome oxidase and ADP/ATP translocase) were present in 2-4 times higher amounts in the poly(A)-rich RNA of the hepatoma than in the corresponding RNA fraction from resting or regenerating rat liver. The liver and hepatoma transcripts for the beta-F1 subunit were translated in an in-vitro system with equal efficiency. Pulse-chase labeling of isolated Zajdela hepatoma cells and hepatocytes from resting and regenerating liver revealed a relative excess of the newly synthesized beta-F1 subunit in the tumor cells. The half-life of the beta-F1 subunit was significantly shorter in the hepatoma cells than in hepatocytes from resting and regenerating liver. The contents of transcripts of three mitochondrial genes examined (cytochrome oxidase subunits I and II and NADH-ubiquinone reductase subunit 2) in Zajdela hepatoma mitochondria were about five-times higher than in the mitochondria of the resting cells and 3-4 times higher than in the organelles of the regenerating organ. The results indicate that events other than transcription (most likely post-translational) may be responsible for the reduced content of mitochondria in tumor cells.
- MeSH
- buněčné jádro metabolismus MeSH
- DNA sondy MeSH
- experimentální nádory jater enzymologie metabolismus MeSH
- genetická transkripce * MeSH
- inbrední kmeny potkanů MeSH
- jaderné proteiny genetika MeSH
- jaterní mitochondrie metabolismus MeSH
- játra cytologie enzymologie fyziologie MeSH
- krysa rodu Rattus MeSH
- messenger RNA MeSH
- mitochondriální DNA genetika MeSH
- northern blotting MeSH
- poly A genetika MeSH
- proteosyntéza MeSH
- protonové ATPasy biosyntéza MeSH
- pulzní gelová elektroforéza MeSH
- regenerace jater MeSH
- RNA genetika MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- DNA sondy MeSH
- jaderné proteiny MeSH
- messenger RNA MeSH
- mitochondriální DNA MeSH
- poly A MeSH
- protonové ATPasy MeSH
- RNA MeSH
In order to characterize the biogenesis of unique thermogenic mitochondria of brown adipose tissue, differentiation of precursor cells isolated from mouse brown adipose tissue was studied in cell culture. Synthesis of mitochondrial uncoupling protein (UCP), F1-ATPase, and cytochrome oxidase was examined by L-[35S]methionine labeling and immunoblotting. For the first time, synthesis of physiological amounts of the UCP, a key and tissue-specific component of thermogenic mitochondria, was observed in cultures at about confluence (day 6), indicating that a complete differentiation of brown adipocytes was achieved in vitro. In postconfluent cells (day 8) the content of UCP decreased rapidly, in contrast to some other mitochondrial proteins (beta subunit of F1-ATPase, cytochrome oxidase). In these cells, it was possible, by using norepinephrine, to induce specifically the synthesis of the UCP but not of F1-ATPase or cytochrome oxidase. The maximal response was observed at 0.1 microM norepinephrine and the synthesis of UCP remained activated for at least 24 h. Detailed analysis revealed a major role of the beta-adrenergic receptors and elevated intracellular concentration of cAMP in stimulation of UCP synthesis. A quantitative recovery of the newly synthesized UCP in the mitochondrial fraction indicated completed biogenesis of functionally competent thermogenic mitochondria.
- MeSH
- 2D gelová elektroforéza MeSH
- buněčná diferenciace MeSH
- hnědá tuková tkáň cytologie metabolismus MeSH
- iontové kanály MeSH
- kinetika MeSH
- kultivované buňky MeSH
- membránové proteiny biosyntéza izolace a purifikace MeSH
- methionin metabolismus MeSH
- mitochondriální proteiny MeSH
- mitochondrie metabolismus MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- protonové ATPasy biosyntéza izolace a purifikace MeSH
- radioizotopy síry MeSH
- respirační komplex IV biosyntéza izolace a purifikace MeSH
- transportní proteiny * MeSH
- uncoupling protein 1 MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- iontové kanály MeSH
- membránové proteiny MeSH
- methionin MeSH
- mitochondriální proteiny MeSH
- protonové ATPasy MeSH
- radioizotopy síry MeSH
- respirační komplex IV MeSH
- transportní proteiny * MeSH
- uncoupling protein 1 MeSH