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Houstĕk J, Tvrdík P, Pavelka S, Baudysová M. Low content of mitochondrial ATPase in brown adipose tissue is the result of post-transcriptional regulation. FEBS Lett 1991; 294:191-4. [PMID: 1661683 DOI: 10.1016/0014-5793(91)80666-q] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The mRNA levels of ATPase beta, ATPase 6, cytochrome oxidase (COX) VIb and COX I subunits were found to be 2.4-13.8-fold higher in brown adipose tissue (BAT) than in heart, skeletal muscle, brain and liver of mice. The comparison with tissue contents of ATPase and COX revealed that the selective, 5-11-fold reduction of ATPase in BAT is not caused by decreased transcription of ATPase genes. Likewise, the ATPase beta and COX VIb mRNA levels in cultured brown adipocytes were also not influenced by norepinephrine, which activated the expression of the UCP gene by two orders of magnitude. The results indicate that the biosynthesis of mitochondrial ATPase in BAT is post-transcriptionally regulated.
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Affiliation(s)
- J Houstĕk
- Institute of Physiology, Czechoslovak Academy of Sciences, Prague
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Affiliation(s)
- R A Capaldi
- Institute of Molecular Biology, University of Oregon, Eugene 97403
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Houstĕk J, Janíková D, Bednár J, Kopecký J, Sebestián J, Soukup T. Postnatal appearance of uncoupling protein and formation of thermogenic mitochondria in hamster brown adipose tissue. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1015:441-9. [PMID: 2154254 DOI: 10.1016/0005-2728(90)90077-h] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Brown adipose tissue of developing hamster was characterized by western blotting, enzyme activity measurements and immunoelectron microscopy. During the first postnatal week the tissue contained significant amounts of differentiating mitochondria and comparable quantities of active cytochrome oxidase and ATP synthase. The uncoupling protein appeared on the 7/8th day and its specific content increased 80-times between day 8 and day 17. In parallel, the specific content and activity of cytochrome oxidase increased 3-times but ATP synthase decreased 2-times. The total content of uncoupling protein and of cytochrome oxidase in interscapular brown adipose tissue increased 360- and 11-times, respectively. Analysis of isolated mitochondria showed that the observed differences result mainly from changes of the enzymic equipment of the mitochondrial membrane. During the same interval, propylthiouracil-insensitive "type II' thyroxine 5'-deiodinase activity in brown adipose tissue increased 10-times. It was concluded that the thermogenic function of the hamster brown adipose tissue develops after the first postnatal week due to highly differentiated synthesis of mitochondrial proteins leading to replacement of preexisting, uncoupling protein-lacking nonthermogenic mitochondria by thermogenic ones, similarly as shown in brown adipose tissue of the embryonic mouse and rat (Houstĕk, J., et al. (1988) Biochim. Biophys. Acta 935, 19-25).
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Affiliation(s)
- J Houstĕk
- Institute of Physiology, Czechoslovak Academy of Sciences, Prague
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Houstĕk J, Kopecký J, Rychter Z, Soukup T. Uncoupling protein in embryonic brown adipose tissue--existence of nonthermogenic and thermogenic mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 935:19-25. [PMID: 2900653 DOI: 10.1016/0005-2728(88)90103-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Embryonic development of mouse and rat brown adipose tissue was characterized by electron microscopy and by quantifying the mitochondrial oxidative, phosphorylating and thermogenic capacities immunochemically, using antibodies against cytochrome oxidase, F1-ATPase and uncoupling protein, respectively. Mitochondria and cytochrome oxidase were detected from the 15-16th day of pregnancy and their amounts continuously increased toward birth. F1-ATPase was also found on the 15th day but it reached a maximum level already on the 19th day when the uncoupling protein appeared and rapidly increased during further maturation of brown adipose tissue. It thus appears that mitochondria in early prenatal brown adipose tissue lack completely uncoupling protein and are nonthermogenic. They transform into typical thermogenic mitochondria abruptly only 2 days before birth.
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Affiliation(s)
- J Houstĕk
- Institute of Physiology, Czechoslovak Academy of Sciences, Prague
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Biogenesis of Mammalian Mitochondria. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/b978-0-12-152515-6.50012-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Evolution of a Regulatory Enzyme: Cytochrome-c Oxidase (Complex IV). CURRENT TOPICS IN BIOENERGETICS - STRUCTURE, BIOGENESIS, AND ASSEMBLY OF ENERGY TRANSDUCING ENZYME SYSTEMS 1987. [DOI: 10.1016/b978-0-12-152515-6.50009-6] [Citation(s) in RCA: 145] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Johansson T, Berrez JM, Nelson BD. Evidence that transcription of the hexokinase gene is increased in a rapidly growing rat hepatoma. Biochem Biophys Res Commun 1985; 133:608-13. [PMID: 4084289 DOI: 10.1016/0006-291x(85)90948-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The level of hexokinase-specific mRNA in rat liver and in rat ascites hepatoma (Zajdela) was assessed by translating free polysomes from both cell types in a reticulocyte lysate. Translation of hexokinase occurred with approximately a 10 fold higher frequency in tumor cells than in liver, suggesting that transcriptional activation is in part responsible for increased levels of hexokinase in tumor.
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Carlenor E, Joste V, Nelson BD, Rydström J. Cell-free translation of mitochondrial nicotinamide nucleotide transhydrogenase. Biosci Rep 1985; 5:483-90. [PMID: 4041564 DOI: 10.1007/bf01116947] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mammalian nicotinamide nucleotide transhydrogenase is translated as a 5000 daltons larger molecular weight precursor in a cell-free system programmed with rat liver polysomes. The mature rat liver enzyme had the same molecular weight as the purified beef heart enzyme, 115 000 daltons. The precursor was not processed in vitro by liver mitochondria or by a rat liver mitochondrial matrix fraction, nor did it appear to bind to mitochondria. In contrast, pre-FeS protein of the cytochrome bc1 complex was processed in the same samples by both mitochondria and matrix, suggesting an important difference in the processing mechanisms or in the efficiency of processing of the two precursors.
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Kolarov J, Hatalová I. Coupling between proteolytic processing and translocation of the precursor of the F1-ATPase beta-subunit during its import into mitochondria of intact cells. FEBS Lett 1984; 178:161-4. [PMID: 6238846 DOI: 10.1016/0014-5793(84)81262-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The intracellular transport of newly synthesized beta-subunits of the F1-ATPase (beta F1) and of newly synthesized ADP/ATP carrier was followed in isolated rat hepatoma cells. As tested by rapid fractionation of [35S]methionine pulse- and pulse-chase-labeled cells and by sensitivity of labeled polypeptides to externally added protease, the import of beta F1 into mitochondria was strongly inhibited by the additional low concentrations of rhodamine 6G (R6G). In contrast, the import of the ADP/ATP carrier into mitochondria was not affected by the inhibitor. The results imply that the proteolytic processing of the precursor of beta F1 is coupled to its translocation across the mitochondrial membrane.
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Wielburski A, Nelson BD. Heme a induces assembly of rat liver cytochrome c oxidase subunits I--III in isolated mitochondria. FEBS Lett 1984; 177:291-4. [PMID: 6094250 DOI: 10.1016/0014-5793(84)81302-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The assembly of cytochrome c oxidase subunits I-III was studied in vitro in isolated rat liver mitochondria pre-labeled with [35S]methionine. Individual subunits were immunoabsorbed with monospecific antibodies. Isolated heme a from rat liver mitochondria, when added to radiolabeled mitochondria, induced assembly of subunit I with subunits II and III. Assembly of these subunits was not observed in mitochondria incubated in the presence of heme b(hemin) or in the absence of heme. Quantitative analysis of immunoabsorbed, radiolabeled subunits suggests that the predominant effect of heme a is on the assembly of subunit I with subunit III.
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Kolarov J, Nelson BD. Import and processing of cytochrome b-c1 complex subunits in isolated hepatoma ascites cells. Inhibition by Rhodamine 6G. EUROPEAN JOURNAL OF BIOCHEMISTRY 1984; 144:387-92. [PMID: 6092071 DOI: 10.1111/j.1432-1033.1984.tb08476.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The import and processing of cytochrome c1 and the iron sulfur protein of the cytochrome b-c1 complex were studied in Zajdela hepatoma ascites cells. Both peptides were synthesized as larger percursor molecules which were approximately 2-3 kDa and 5-6 kDa larger than the mature forms of apocytochrome c1 and apo-iron sulfur protein, respectively. Comparison of these precursors to those reported for functionally homologous peptides in yeast and Neurospora indicate significant size changes have occurred in mammals. Rhodamine 6G, a specific vital stain for mitochondria, is a potent inhibitor of precursor processing in isolated hepatoma cells. Both precursor to cytochrome c1 and precursor to FeS accumulate in the soluble and particulate fractions obtained by digitonin treatment of tumor cells treated with Rhodamine 6G. Appearance of the mature peptides was abolished. The precursors are unstable, however, and disappear from the cytosolic and membrane fractions during a 10 min chase. Comparison of the effects of Rhodamine 6G and carbonylcyanide m-chlorophenylhydrazone on precursor processing shows that: (a) Rhodamine 6G is a more effective inhibitor of processing, (b) it has less of an inhibitory effect on cellular protein synthesis, and (c) it inhibits processing under conditions in which it appears to have little influence on coupled respiration in whole cells. The data suggest that the most likely mode of action of Rhodamine 6G is on the matrix processing step.
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Kolarov J, Nelson BD, Kuzela S. Rat liver protoporphyrinogen IX oxidase: site of synthesis and factor influencing its activity. Biochem Biophys Res Commun 1983; 116:383-7. [PMID: 6316951 DOI: 10.1016/0006-291x(83)90533-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Rat liver protoporphyrinogen IX oxidase is not formed in mitochondria in contrast to the claims made for the yeast enzyme (Poulson and Polglase, FEBS Lett. (1974) 40, 258). Inhibition of mitochondrial protein synthesis in regenerating rat livers by thiamphenicol led, instead, to a slight increase in protoporphyrinogen oxidase activity. Protoporphyrinogen IX oxidase was not induced in rat liver by triiodothyronine, an inducer of mitochondrial protein synthesis, or by AIA, an inducer of heme synthesis. Significant increases in activity were observed to be associated with rapidly growing cells, such as regenerating livers and rat ascites hepatoma cells.
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Wielburski A, Nelson BD. Evidence for the sequential assembly of cytochrome oxidase subunits in rat liver mitochondria. Biochem J 1983; 212:829-34. [PMID: 6309154 PMCID: PMC1153160 DOI: 10.1042/bj2120829] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The assembly of cytochrome oxidase was studied in isolated rat liver mitochondria and isolated rat hepatocytes labelled in vitro with L-[35S]methionine. This was achieved by studying the temporal association of radioactive subunits which are immunoabsorbed with antibodies against subunits I, II and the holoenzyme. Antibodies against the holoenzyme were shown to be highly specific for subunit V. The results show that subunit I appears in the holoenzyme late in the assembly process. No radioactive subunit I is absorbed with antiserum against subunit II or the holoenzyme (subunit V) after a 30 min pulse in either isolated mitochondria or hepatocytes. However, both antisera absorb radioactive subunits I after a 150 min chase in isolated hepatocytes. This was confirmed using antibodies against subunit I, which absorbed only radioactive subunit I after a 30 min pulse but absorbed radioactive subunits I-III and VI after a 150 min chase. Thus, the late assembly of radioactive subunit I is explained by a temporal sequence in the assembly process and not by the presence of a large, non-radioactive pool of subunit I. Using the above approach and the three specific antisera, the following temporal sequence in the assembly of cytochrome oxidase was established. Subunits II and III assemble rapidly with each other or with cytoplasmically translated subunit VI. This complex of three peptides in turn assembles slowly with subunit I or with the other cytoplasmically translated subunits. The early association of subunit VI with the mitochondrially translated subunits II and III suggests a possible role of the former in integration of the holoenzyme.
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Kadenbach B. Structure and Evolution of the ?Atmungsferment? Cytochrome c Oxidase. ACTA ACUST UNITED AC 1983. [DOI: 10.1002/anie.198302751] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Hatalová I, Kolarov J. Synthesis and intracellular transport of cytochrome oxidase subunit IV and ADP/ATP translocator protein in intact hepatoma cells. Biochem Biophys Res Commun 1983; 110:132-9. [PMID: 6301438 DOI: 10.1016/0006-291x(83)91270-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The biosynthesis of two mitochondrial membrane proteins - subunit IV of cytochrome oxidase and ADP/ATP translocator protein was studied in intact ascites hepatoma cells. Using pulse-chase labeling and rapid cell fractionation it was possible to identify the precursoric forms of these inner mitochondrial membrane proteins. It was found that the subunit IV of cytochrome oxidase is synthesized in the cytoplasm of mammalian cells in the form of a larger precursor while ADP/ATP translocator protein is synthesized in the form that is electrophoretically undistinguishable from the mature membrane integrated form.
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Parimoo S, Rao N, Padmanaban G. Cytochrome c oxidase is preferentially synthesized in the rough endoplasmic reticulum--mitochondrion complex in rat liver. Biochem J 1982; 208:505-7. [PMID: 6297469 PMCID: PMC1153990 DOI: 10.1042/bj2080505] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The specific activity and content of cytochrome oxidase in the rough endoplasmic reticulum--mitochondrion complex are higher than in the mitochondrial fraction. Radiolabelling studies with the use of hepatocytes and isolated microsomal and rough endoplasmic reticulum--mitochondrion fractions, followed by immunoprecipitation with anti-(cytochrome oxidase) antibody, reveal that the nuclear-coded cytoplasmic subunits of cytochrome oxidase are preferentially synthesized in the latter fraction. The results have a bearing on the mechanism of transport of these subunits into mitochondria.
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In vivo biosynthesis of the vacuolar proteinases A and B in the yeast Saccharomyces cerevisiae. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)33740-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Heinrich PC. Proteolytic processing of polypeptides during the biosynthesis of subcellular structures. Rev Physiol Biochem Pharmacol 1982; 93:115-87. [PMID: 7048487 DOI: 10.1007/bfb0032670] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Müller M, Müller H. Synthesis and processing of in vitro and in vivo precursors of the vacuolar yeast enzyme carboxypeptidase Y. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(18)43213-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Kadenbach B, Merle P. On the function of multiple subunits of cytochrome c oxidase from higher eukaryotes. FEBS Lett 1981; 135:1-11. [PMID: 6274682 DOI: 10.1016/0014-5793(81)80932-5] [Citation(s) in RCA: 168] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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