Overexpressed Human Mitochondrial Thioredoxin Confers Resistance to Oxidant-induced Apoptosis in Human Osteosarcoma Cells

Abstract

Oxidative damage to mitochondria is a central mechanism of apoptosis induced by many toxic chemicals. Thioredoxin family proteins share a conserved Cys-X-X-Cys motif at their active center and play important roles in control of cellular redox state and protection against oxidative damage. In addition to the well studied cytosolic and extracellular form (Trx1), rat and avian mitochondrial forms of thioredoxin (mtTrx) have been reported. In this study, we cloned the full-length human mtTrx cDNA and performed localization and functional studies in 143B human osteosarcoma cells. The coding sequence of human mtTrx consists of a region with homology to Trx1 as well as a putative mitochondrial localization signal (MLS) at its N terminus. In stably transfected cell lines, mtTrx had a mitochondrial localization as measured by subcellular fractionation studies and by confocal fluorescence microscopy. Deletion of the MLS rendered mtTrx to be solely expressed in the cytosolic fraction. On SDS-PAGE, transfected mtTrx had the same apparent molecular weight as the MLS truncated form, indicating that the leader sequence is cleaved during or after mitochondrial import. Treatment with the oxidant tert-butylhydroperoxide induced apoptosis in 143B cells. This oxidant-induced apoptosis was inhibited by overexpressing the full-length mtTrx in 143B cells. Thus, human mtTrx is a member of the thioredoxin family of proteins localized to mitochondria and may play important roles in protection against oxidant-induced apoptosis. Oxidative damage to mitochondria is a central mechanism of apoptosis induced by many toxic chemicals. Thioredoxin family proteins share a conserved Cys-X-X-Cys motif at their active center and play important roles in control of cellular redox state and protection against oxidative damage. In addition to the well studied cytosolic and extracellular form (Trx1), rat and avian mitochondrial forms of thioredoxin (mtTrx) have been reported. In this study, we cloned the full-length human mtTrx cDNA and performed localization and functional studies in 143B human osteosarcoma cells. The coding sequence of human mtTrx consists of a region with homology to Trx1 as well as a putative mitochondrial localization signal (MLS) at its N terminus. In stably transfected cell lines, mtTrx had a mitochondrial localization as measured by subcellular fractionation studies and by confocal fluorescence microscopy. Deletion of the MLS rendered mtTrx to be solely expressed in the cytosolic fraction. On SDS-PAGE, transfected mtTrx had the same apparent molecular weight as the MLS truncated form, indicating that the leader sequence is cleaved during or after mitochondrial import. Treatment with the oxidant tert-butylhydroperoxide induced apoptosis in 143B cells. This oxidant-induced apoptosis was inhibited by overexpressing the full-length mtTrx in 143B cells. Thus, human mtTrx is a member of the thioredoxin family of proteins localized to mitochondria and may play important roles in protection against oxidant-induced apoptosis. thioredoxin thioredoxin reductase reactive oxygen species apoptosis signal-regulating kinase tert-butylhydroperoxide mitochondrial thioredoxin rapid amplification of cDNA ends green fluorescent protein tetramethylrhodamine methyl ester phosphate-buffered saline reverse transcription mitochondria localization signal mitochondrial permeability transition Thioredoxins (Trx)1 are a family of small proteins that contain a conserved redox active center, Trp-Cys-Gly-Pro-Cys-Lys (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). The reversible oxidation/reduction in the active center enables Trx to transfer electrons to protein disulfide substrates. Two other components, thioredoxin reductase (TR) and NADPH, reduce the oxidized Trx and complete Trx cycling (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). In the presence of TR and NADPH, Trx mediates rapid and reversible disulfide-thiol exchange of dithiol motifs in protein substrates. Although Trx was originally identified as an electron donor of ribonucleotide reductase, a wide range of other biological functions have been characterized based on its redox capability (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). Interestingly, Trx is implicated in apoptosis regulation through two different mechanisms: 1) scavenging reactive oxygen species (ROS) to protect against oxidative stress (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar) and 2) direct binding and inhibiting the activity of the proapoptotic protein apoptosis signal-regulating kinase 1 (ASK1) (2Saitoh M. Nishitoh H. Fujii M. Takeda K. Tobiume K. Sawada Y. Kawabata M. Miyazono K. Ichijo H. EMBO J. 1998; 17: 2596-2606Crossref PubMed Scopus (2056) Google Scholar, 3Liu H. Nishitoh H. Ichijo H. Kyriakis J.M. Mol. Cell. Biol. 2000; 20: 2198-2208Crossref PubMed Scopus (443) Google Scholar). Regulating the activities of transcription factors, such as NF-κB and AP-1, is another important aspect of its biological functions (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar).Multiple isoforms of Trx have been identified in different organisms, ranging from Escherichia coli to mammalian cells (4Miranda-Vizuete A. Damdimopoulos A.E. Gustafsson J. Spyrou G. J. Biol. Chem. 1997; 272: 30841-30847Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). In higher organisms, Trx has different subcellular localizations, including cytoplasm, nuclei, and mitochondria (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). The mitochondrial thioredoxin gene was cloned from rat and chicken (9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar), and the protein has been purified from bovine and swine (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar). Like its cytosolic homolog, mtTrx can reduce insulin in vitro, suggesting that proteins share similar biological properties (10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). The cloning of mitochondrial TR (11Miranda-Vizuete A. Damdimopoulos A.E. Pedrajas J.R. Gustafsson J.A. Spyrou G. Eur. J. Biochem. 1999; 261: 405-412Crossref PubMed Scopus (148) Google Scholar, 12Lee S.R. Kim J.R. Kwon K.S. Yoon H.W. Levine R.L. Ginsburg A. Rhee S.G. J. Biol. Chem. 1999; 274: 4722-4734Abstract Full Text Full Text PDF PubMed Scopus (240) Google Scholar) indicates that a complete system of thioredoxin exists in mitochondria, which may play potentially important physiological roles, particularly in protection against oxidants and other forms of chemical-induced toxicities. This is further supported by the recent finding that chicken cells lacking mtTrx showed increased spontaneous apoptosis and were more sensitive to serum deprivation-induced apoptosis (9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar).In this study, we cloned the human mtTrx and determined that it is specifically localized in mitochondria. Northern blot analysis revealed the existence of two forms of human mtTrx mRNA and demonstrated that it is widely expressed in human tissues. The two forms of the mtTrx transcript differ in the of human mtTrx in 143B osteosarcoma cells cells from cell induced by the that the mtTrx system may an important mechanism that functions in mitochondria to protect against oxidative stress and exists in more form in species and in higher (4Miranda-Vizuete A. Damdimopoulos A.E. Gustafsson J. Spyrou G. J. Biol. Chem. 1997; 272: 30841-30847Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar, K. M. S. Nishiyama A. K. Yodoi J. Proc. Natl. Acad. Sci. U. S. A. 1997; PubMed Scopus Google Scholar). of the Trx has been to protect against oxidative This with the conserved of mtTrx (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) that mtTrx may have important biological functions in protection against oxidative stress in the analysis indicates that are two mRNA that are different in the of the The is in with the mtTrx sequence that it the The has an of the sequence and the signal and at the such signal exists in the cDNA a which is the in is that and that an signal is the cDNA Northern blot analysis showed that two were in and that the molecular were to of the two cDNA from and that the two mRNA species are to in studies a in with a in and are with Northern blot of mtTrx in rat (10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) in which in with of the of with mitochondrial increased of mtTrx with to protect against the protein redox and control the cellular to studies with of mitochondrial that the oxidant M. Sci. 1999; Google Scholar, S. J.R. F. K. Sci. 2001; PubMed Scopus Google Scholar) mitochondria M. Chem. Toxicol. PubMed Scopus Google Scholar). apoptosis the mitochondrial in which the mitochondrial permeability transition is Biol. 1998; PubMed Scopus Google Scholar), is and is M. Sci. 1999; Google Scholar). The that cells were against the cell This protection be through a direct in with J. Biol. 2001; PubMed Scopus Google Scholar, Kim K. Rhee S.G. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google in of of was control and apoptosis by the redox state of mitochondrial an important of the that are to redox regulation N. N. C. G. 2000; PubMed Scopus Google Scholar, F. E. C. G. C. G. 2001; 20: PubMed Scopus Google Scholar). mtTrx may with the and the of the indicates that redox control of the may be a of a to to and E. J. 1999; PubMed Scopus Google Scholar, 1998; PubMed Scopus Google Scholar, 1999; PubMed Scopus Google Scholar).In the that the human mtTrx is expressed as two mRNA species that differ in of the mRNA was in and in other tissues. mtTrx protein was to mitochondria, and of this protein against oxidant-induced apoptosis. that in addition to the well studied and protein human mitochondria contain a functional system protection against oxidative damage and oxidant-induced apoptosis. Thioredoxins (Trx)1 are a family of small proteins that contain a conserved redox active center, Trp-Cys-Gly-Pro-Cys-Lys (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). The reversible oxidation/reduction in the active center enables Trx to transfer electrons to protein disulfide substrates. Two other components, thioredoxin reductase (TR) and NADPH, reduce the oxidized Trx and complete Trx cycling (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). In the presence of TR and NADPH, Trx mediates rapid and reversible disulfide-thiol exchange of dithiol motifs in protein substrates. Although Trx was originally identified as an electron donor of ribonucleotide reductase, a wide range of other biological functions have been characterized based on its redox capability (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). Interestingly, Trx is implicated in apoptosis regulation through two different mechanisms: 1) scavenging reactive oxygen species (ROS) to protect against oxidative stress (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar) and 2) direct binding and inhibiting the activity of the proapoptotic protein apoptosis signal-regulating kinase 1 (ASK1) (2Saitoh M. Nishitoh H. Fujii M. Takeda K. Tobiume K. Sawada Y. Kawabata M. Miyazono K. Ichijo H. EMBO J. 1998; 17: 2596-2606Crossref PubMed Scopus (2056) Google Scholar, 3Liu H. Nishitoh H. Ichijo H. Kyriakis J.M. Mol. Cell. Biol. 2000; 20: 2198-2208Crossref PubMed Scopus (443) Google Scholar). Regulating the activities of transcription factors, such as NF-κB and AP-1, is another important aspect of its biological functions (1Powis G. Montfort W.R. Annu. Rev. Pharmacol. Toxicol. 2001; 41: 261-295Crossref PubMed Scopus (330) Google Scholar). isoforms of Trx have been identified in different organisms, ranging from Escherichia coli to mammalian cells (4Miranda-Vizuete A. Damdimopoulos A.E. Gustafsson J. Spyrou G. J. Biol. Chem. 1997; 272: 30841-30847Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). In higher organisms, Trx has different subcellular localizations, including cytoplasm, nuclei, and mitochondria (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). The mitochondrial thioredoxin gene was cloned from rat and chicken (9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar), and the protein has been purified from bovine and swine (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar). Like its cytosolic homolog, mtTrx can reduce insulin in vitro, suggesting that proteins share similar biological properties (10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar). The cloning of mitochondrial TR (11Miranda-Vizuete A. Damdimopoulos A.E. Pedrajas J.R. Gustafsson J.A. Spyrou G. Eur. J. Biochem. 1999; 261: 405-412Crossref PubMed Scopus (148) Google Scholar, 12Lee S.R. Kim J.R. Kwon K.S. Yoon H.W. Levine R.L. Ginsburg A. Rhee S.G. J. Biol. Chem. 1999; 274: 4722-4734Abstract Full Text Full Text PDF PubMed Scopus (240) Google Scholar) indicates that a complete system of thioredoxin exists in mitochondria, which may play potentially important physiological roles, particularly in protection against oxidants and other forms of chemical-induced toxicities. This is further supported by the recent finding that chicken cells lacking mtTrx showed increased spontaneous apoptosis and were more sensitive to serum deprivation-induced apoptosis (9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar). In this study, we cloned the human mtTrx and determined that it is specifically localized in mitochondria. Northern blot analysis revealed the existence of two forms of human mtTrx mRNA and demonstrated that it is widely expressed in human tissues. The two forms of the mtTrx transcript differ in the of human mtTrx in 143B osteosarcoma cells cells from cell induced by the that the mtTrx system may an important mechanism that functions in mitochondria to protect against oxidative stress and apoptosis. exists in more form in species and in higher (4Miranda-Vizuete A. Damdimopoulos A.E. Gustafsson J. Spyrou G. J. Biol. Chem. 1997; 272: 30841-30847Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar, K. M. S. Nishiyama A. K. Yodoi J. Proc. Natl. Acad. Sci. U. S. A. 1997; PubMed Scopus Google Scholar). of the Trx has been to protect against oxidative This with the conserved of mtTrx (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) that mtTrx may have important biological functions in protection against oxidative stress in the analysis indicates that are two mRNA that are different in the of the The is in with the mtTrx sequence that it the The has an of the sequence and the signal and at the such signal exists in the cDNA a which is the in is that and that an signal is the cDNA Northern blot analysis showed that two were in and that the molecular were to of the two cDNA from and that the two mRNA species are to in studies a in with a in and are with Northern blot of mtTrx in rat (10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) in which in with of the of with mitochondrial increased of mtTrx with to protect against the protein redox and control the cellular to studies with of mitochondrial that the oxidant M. Sci. 1999; Google Scholar, S. J.R. F. K. Sci. 2001; PubMed Scopus Google Scholar) mitochondria M. Chem. Toxicol. PubMed Scopus Google Scholar). apoptosis the mitochondrial in which the mitochondrial permeability transition is Biol. 1998; PubMed Scopus Google Scholar), is and is M. Sci. 1999; Google Scholar). The that cells were against the cell This protection be through a direct in with J. Biol. 2001; PubMed Scopus Google Scholar, Kim K. Rhee S.G. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google in of of was control and apoptosis by the redox state of mitochondrial an important of the that are to redox regulation N. N. C. G. 2000; PubMed Scopus Google Scholar, F. E. C. G. C. G. 2001; 20: PubMed Scopus Google Scholar). mtTrx may with the and the of the indicates that redox control of the may be a of a to to and E. J. 1999; PubMed Scopus Google Scholar, 1998; PubMed Scopus Google Scholar, 1999; PubMed Scopus Google Scholar).In the that the human mtTrx is expressed as two mRNA species that differ in of the mRNA was in and in other tissues. mtTrx protein was to mitochondria, and of this protein against oxidant-induced apoptosis. that in addition to the well studied and protein human mitochondria contain a functional system protection against oxidative damage and oxidant-induced apoptosis. Trx exists in more form in species and in higher (4Miranda-Vizuete A. Damdimopoulos A.E. Gustafsson J. Spyrou G. J. Biol. Chem. 1997; 272: 30841-30847Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 7Pedrajas J.R. Kosmidou E. Miranda-Vizuete A. Gustafsson J.A. Wright A.P. Spyrou G. J. Biol. Chem. 1999; 274: 6366-6373Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar, 8Laloi C. Rayapurmi N. Chartier Y. Grienenberger J. Bonnard G. Meyer Y. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 14144-14149Crossref PubMed Scopus (222) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar, K. M. S. Nishiyama A. K. Yodoi J. Proc. Natl. Acad. Sci. U. S. A. 1997; PubMed Scopus Google Scholar). of the Trx has been to protect against oxidative This with the conserved of mtTrx (5Bodenstein-Lang J. Buch A. Follmann H. FEBS Lett. 1989; 258: 22-26Crossref PubMed Scopus (66) Google Scholar, 6Watabe S. Hiroi T. Yamamoto Y. Fujioka Y. Hasegawa H. Yago N. Takahashi S.Y. Eur. J. Biochem. 1997; 249: 52-60Crossref PubMed Scopus (131) Google Scholar, 9Tanaka T. Hosoi F. Yamaguchi-Iwai Y. Nakamura H. Masutani H. Udea S. Nishiyama A. Takeda S. Wada H. Spyrou G. Yodoi J. EMBO J. 2002; 21: 1695-1703Crossref PubMed Scopus (279) Google Scholar, 10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) that mtTrx may have important biological functions in protection against oxidative stress in the mitochondria. The analysis indicates that are two mRNA that are different in the of the The is in with the mtTrx sequence that it the The has an of the sequence and the signal and at the such signal exists in the cDNA a which is the in is that and that an signal is the cDNA Northern blot analysis showed that two were in and that the molecular were to of the two cDNA from and that the two mRNA species are to in studies a in with a in and are with Northern blot of mtTrx in rat (10Spyrou G. Enmark E. Miranda-Vizuete A. Gustafsson J. J. Biol. Chem. 1997; 272: 2936-2941Abstract Full Text Full Text PDF PubMed Scopus (329) Google Scholar) in which in with of the of with mitochondrial increased of mtTrx with to protect against the protein redox and control the cellular to apoptosis. studies with of mitochondrial that the oxidant M. Sci. 1999; Google Scholar, S. J.R. F. K. Sci. 2001; PubMed Scopus Google Scholar) mitochondria M. Chem. Toxicol. PubMed Scopus Google Scholar). apoptosis the mitochondrial in which the mitochondrial permeability transition is Biol. 1998; PubMed Scopus Google Scholar), is and is M. Sci. 1999; Google Scholar). The that cells were against the cell This protection be through a direct in with J. Biol. 2001; PubMed Scopus Google Scholar, Kim K. Rhee S.G. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google in of of was control and cells. mtTrx apoptosis by the redox state of mitochondrial an important of the that are to redox regulation N. N. C. G. 2000; PubMed Scopus Google Scholar, F. E. C. G. C. G. 2001; 20: PubMed Scopus Google Scholar). mtTrx may with the and the of the indicates that redox control of the may be a of a to to and E. J. 1999; PubMed Scopus Google Scholar, 1998; PubMed Scopus Google Scholar, 1999; PubMed Scopus Google Scholar). In the that the human mtTrx is expressed as two mRNA species that differ in of the mRNA was in and in other tissues. mtTrx protein was to mitochondria, and of this protein against oxidant-induced apoptosis. that in addition to the well studied and protein human mitochondria contain a functional system protection against oxidative damage and oxidant-induced apoptosis. cells. and the on the