AtGRXcp, an Arabidopsis Chloroplastic Glutaredoxin, Is Critical for Protection against Protein Oxidative Damage

Abstract

Glutaredoxins (Grxs) are ubiquitous small heat-stable disulfide oxidoreductases and members of the thioredoxin (Trx) fold protein family. In bacterial, yeast, and mammalian cells, Grxs appear to be involved in maintaining cellular redox homeostasis. However, in plants, the physiological roles of Grxs have not been fully characterized. Recently, an emerging subgroup of Grxs with one cysteine residue in the putative active motif (monothiol Grxs) has been identified but not well characterized. Here we demonstrate that a plant protein, AtGRXcp, is a chloroplast-localized monothiol Grx with high similarity to yeast Grx5. In yeast expression assays, AtGRXcp localized to the mitochondria and suppressed the sensitivity of yeast grx5 cells to H2O2 and protein oxidation. AtGRXcp expression can also suppress iron accumulation and partially rescue the lysine auxotrophy of yeast grx5 cells. Analysis of the conserved monothiol motif suggests that the cysteine residue affects AtGRXcp expression and stability. In planta, AtGRXcp expression was elevated in young cotyledons, green tissues, and vascular bundles. Analysis of atgrxcp plants demonstrated defects in early seedling growth under oxidative stresses. In addition, atgrxcp lines displayed increased protein carbonylation within chloroplasts. Thus, this work describes the initial functional characterization of a plant monothiol Grx and suggests a conserved biological function in protecting cells against protein oxidative damage. Glutaredoxins (Grxs) are ubiquitous small heat-stable disulfide oxidoreductases and members of the thioredoxin (Trx) fold protein family. In bacterial, yeast, and mammalian cells, Grxs appear to be involved in maintaining cellular redox homeostasis. However, in plants, the physiological roles of Grxs have not been fully characterized. Recently, an emerging subgroup of Grxs with one cysteine residue in the putative active motif (monothiol Grxs) has been identified but not well characterized. Here we demonstrate that a plant protein, AtGRXcp, is a chloroplast-localized monothiol Grx with high similarity to yeast Grx5. In yeast expression assays, AtGRXcp localized to the mitochondria and suppressed the sensitivity of yeast grx5 cells to H2O2 and protein oxidation. AtGRXcp expression can also suppress iron accumulation and partially rescue the lysine auxotrophy of yeast grx5 cells. Analysis of the conserved monothiol motif suggests that the cysteine residue affects AtGRXcp expression and stability. In planta, AtGRXcp expression was elevated in young cotyledons, green tissues, and vascular bundles. Analysis of atgrxcp plants demonstrated defects in early seedling growth under oxidative stresses. In addition, atgrxcp lines displayed increased protein carbonylation within chloroplasts. Thus, this work describes the initial functional characterization of a plant monothiol Grx and suggests a conserved biological function in protecting cells against protein oxidative damage. Reactive oxygen species (ROS) 2The abbreviations used are: ROS, reactive oxygen species; PICOT-HD, protein kinase C-interacting cousin of thioredoxin homology domain; Grx, glutaredoxin; Trx, thioredoxin; GFP, green fluorescent protein; GUS, β-glucuronidase gene; CaMV, cauliflower mosaic virus promoter. can be formed as by-products in all oxygenic organisms during aerobic metabolism (1Apel K. Hirt H. Annu. Rev. Plant Biol. 2004; 55: 373-399Crossref PubMed Scopus (8734) Google Scholar). In higher plants, chloroplasts and mitochondria are two major organelles that contribute to production of reactive oxygen species during photosynthesis and carbon metabolism (2Vranová E. Inzé D. Van Breusegem F. J. Exp. Bot. 2002; 53: 1227-1236Crossref PubMed Google Scholar, 3Rhoads D.M. Umbach A.L. Chalivendra S.C. Siedow J.N. Plant Physiol. 2006; 141: 357-366Crossref PubMed Scopus (417) Google Scholar). In addition, plants actively generate ROS as signals in response to environmental stresses (3Rhoads D.M. Umbach A.L. Chalivendra S.C. Siedow J.N. Plant Physiol. 2006; 141: 357-366Crossref PubMed Scopus (417) Google Scholar, 4Foyer C.H. Noctor G. Plant Cell. 2005; 17: 1866-1875Crossref PubMed Scopus (2217) Google Scholar, 5Fobert P.R. Després C. Curr. Opin. Plant Biol. 2005; 8: 378-382Crossref PubMed Scopus (119) Google Scholar, 6Gechev T.S. Hille J. J. Cell Biol. 2005; 168: 17-20Crossref PubMed Scopus (417) Google Scholar). However, because of the cytotoxic and extremely reactive nature of ROS, they can cause wide ranging damage to macromolecules (1Apel K. Hirt H. Annu. Rev. Plant Biol. 2004; 55: 373-399Crossref PubMed Scopus (8734) Google Scholar, 7Finkel T. Holbrook N.J. Nature. 2000; 408: 239-247Crossref PubMed Scopus (7610) Google Scholar, 8Nyström T. EMBO J. 2005; 24: 1311-1317Crossref PubMed Scopus (619) Google Scholar, 9Johansson E. Olsson O. Nyström T. J. Biol. Chem. 2004; 279: 22204-22208Abstract Full Text Full Text PDF PubMed Scopus (140) Google Scholar). To overcome such oxidative damage and control signaling events, plants have orchestrated an elaborate antioxidant network (4Foyer C.H. Noctor G. Plant Cell. 2005; 17: 1866-1875Crossref PubMed Scopus (2217) Google Scholar). Of those antioxidant systems, the physiological roles of thioredoxins have been intensively studied (10Buchanan B.B. Balmer Y. Annu. Rev. Plant Biol. 2005; 56: 187-220Crossref PubMed Scopus (720) Google Scholar), whereas those of Grxs have not been fully defined (11Fernandes A.P. Holmgren A. Antioxid. Redox Signal. 2004; 6: 63-74Crossref PubMed Scopus (555) Google Scholar, 12Rouhier N. Gelhaye E. Jacquot J.-P. Cell Mol. Life. Sci. 2004; 61: 1266-1277Crossref PubMed Scopus (182) Google Scholar). Grxs are ubiquitous small heat-stable disulfide oxidoreductases, which are conserved in both prokaryotes and eukaryotes (11Fernandes A.P. Holmgren A. Antioxid. Redox Signal. 2004; 6: 63-74Crossref PubMed Scopus (555) Google Scholar, 13Holmgren A. Åslund F. Methods Enzymol. 1995; 252: 283-292Crossref PubMed Scopus (300) Google Scholar). Through an active motif, namely the conserved CPYC sequence (a dithiol Grx), they catalyze the reduction of protein disulfides and of GSH-protein mixed disulfides via a dithiol or monothiol mechanism (14Holmgren A. J. Biol. Chem. 1989; 264: 13963-13966Abstract Full Text PDF PubMed Google Scholar, 15Bushweller J.H. Åslund F. Wüthrich K. Holmgren A. Biochemistry. 1992; 31: 9288-9293Crossref PubMed Scopus (206) Google Scholar). In bacterial, yeast, and mammalian cells, dithiol Grxs appear to be involved in many cellular processes and play an important role in protecting cells against oxidative stresses (16Ortenberg R. Gon S. Porat A. Beckwith J. Proc. Natl. Acad. Sci. U. S. A. 2004; 101: 7439-7444Crossref PubMed Scopus (56) Google Scholar, 17Grant C.M. Mol. Microbiol. 2001; 39: 533-541Crossref PubMed Scopus (343) Google Scholar, 18Lillig C.H. Berndt C. Vergnolle O. Lönn M.E. Hudemann C. Bill E. Holmgren A. Proc. Natl. Acad. Sci. U. S. A. 2005; 102: 8168-8173Crossref PubMed Scopus (244) Google Scholar). Besides the dithiol Grxs, a new group of monothiol Grxs has recently been identified in yeast (Grx3, -4, and -5) and bacteria (Grx4) that have a single cysteine residue in the putative active motif (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, 20Fernandes A.P. Fladvad M. Berndt C. Andrésen C. Lillig C.H. Neubauer P. Sunnerhagen M. Holmgren A. Vlamis-Gardikas A. J. Biol. Chem. 2005; 280: 24544-24552Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar). Yeast Grx5 encodes a mitochondrial monothiol Grx, which is required for biogenesis of iron-sulfur clusters, whereas Grx3 and Grx4 function in detoxification of cytotoxin and cell proliferation in yeast (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar, 22Jablonowski D. Butler A.R. Fichtner L. Gardiner D. Schaffrath R. Stark M.J.R. Genetics. 2001; 159: 1479-1489Crossref PubMed Google Scholar, 23Lopreiato R. Facchin S. Sartori G. Arrigoni G. Casonato S. Ruzzene M. Pinna L.A. Carignani G. Biochem. J. 2004; 377: 395-405Crossref PubMed Scopus (61) Google Scholar). Interestingly, bacterial Grx4, unlike other previously characterized Grxs, can as a for thioredoxin of A.P. Fladvad M. Berndt C. Andrésen C. Lillig C.H. Neubauer P. Sunnerhagen M. Holmgren A. Vlamis-Gardikas A. J. Biol. Chem. 2005; 280: 24544-24552Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar), that those monothiol Grxs have group of monothiol Grxs is also conserved organisms and has been identified in plants, and S. M. K. Y. N. A. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar, S. M. K. J. Biol. Chem. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar, J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar, H. P. K. 2005; PubMed Scopus Google Scholar). also that those Grxs a identified protein kinase C-interacting cousin of thioredoxin homology in S. M. K. Y. N. A. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar, N. S. A. Biochem. Sci. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar). However, a function of Grxs has been higher plants, have a Grx a plant Grxs have been studied N. Gelhaye E. Jacquot J.-P. Cell Mol. Life. Sci. 2004; 61: 1266-1277Crossref PubMed Scopus (182) Google Scholar, N. Vlamis-Gardikas A. Lillig C.H. Berndt C. Holmgren A. Jacquot J.-P. Antioxid. Redox Signal. PubMed Scopus Google Scholar, 2004; PubMed Scopus (123) Google Scholar). In the are for putative Grxs, which can be major that the monothiol Grxs N. Gelhaye E. Jacquot J.-P. Cell Mol. Life. Sci. 2004; 61: 1266-1277Crossref PubMed Scopus (182) Google Scholar, 2004; PubMed Scopus (123) Google Scholar). of a Grx, an important role of this protein in S. S. 2005; PubMed Scopus Google Scholar). In a we used a yeast functional to a protein that was to in a yeast expression this was J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). Here we the of this plant protein and the as the protein and initial yeast expression to AtGRXcp and the of plants the plant and the we demonstrate a role for a plant monothiol of AtGRXcp atgrxcp two lines the H. P. J. P. R. PubMed Scopus Google Scholar). plants and AtGRXcp and a used to for the AtGRXcp and a used to for the AtGRXcp and the AtGRXcp used to the AtGRXcp of the was the atgrxcp to plants to Plant and atgrxcp and and T. F. Physiol. Scopus Google with and the with of and a G. N. F. F. C. Plant Cell. 2002; PubMed Scopus Google Scholar). and Grx5 was a and a and the of AtGRXcp was a yeast functional and protein J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). AtGRXcp was to have a with the the To this a of AtGRXcp was a and the AtGRXcp was as previously T. K. J. Biol. Chem. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar). and a used for the and the used for the of all was Yeast and grx5 Herrero and used in all yeast Yeast Grx5 and AtGRXcp and S. Proc. Natl. Acad. Sci. U. S. A. 1999; PubMed Scopus Google Scholar). Yeast cells the F. R. K. in Scholar). yeast with or of and or lysine (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar, J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). of in Yeast and Plant and AtGRXcp and to the of green fluorescent protein a previously 2004; PubMed Scopus Google Scholar). yeast and plant expression as previously 2004; PubMed Scopus Google Scholar). of the was in with and as previously 2004; PubMed Scopus Google Scholar). fluorescent was the plant to the of A. J. 1995; Scholar). signals for GFP, for and for the sequence of of AtGRXcp was the and was to the in of plants was as previously T. Plant Cell. PubMed Scopus Google Scholar). plants for for of in both yeast and plant cells as previously (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, E. Methods Enzymol. PubMed Scopus Google Scholar, S. L. H. S. J. K. R. Plant Cell. 2005; 17: PubMed Scopus Google Scholar). Yeast of the and and AtGRXcp in of the of was to with H2O2 for cells with and was used to group chloroplasts of and plants K. Plant J. 2001; PubMed Scopus Google Scholar). protein S. L. H. S. J. K. R. Plant Cell. 2005; 17: PubMed Scopus Google of and and AtGRXcp in of yeast was of and an of was Yeast cells and and and to Sci. Plant 1989; Scholar). To the iron cells and with a and the iron was with a iron AtGRXcp a of the protein was identified function in a yeast J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google we that be as that AtGRXcp is to yeast monothiol Grxs (Grx3, -4, and bacterial Grx4, a and both and Grx5 group of monothiol Grxs also a PICOT-HD, which is conserved in mammalian cells and plants N. S. A. Biochem. Sci. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar). Grxs, yeast Grx3 and -4, and have an AtGRXcp, to the bacterial Grx4, and both yeast and not the (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, 20Fernandes A.P. Fladvad M. Berndt C. Andrésen C. Lillig C.H. Neubauer P. Sunnerhagen M. Holmgren A. Vlamis-Gardikas A. J. Biol. Chem. 2005; 280: 24544-24552Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar, H. P. K. 2005; PubMed Scopus Google Scholar). In addition, suggests that in higher plants, monothiol Grxs in both and In are members of Grxs dithiol Grx has two cysteine in the active motif that are to catalyze protein disulfides and GSH-protein mixed disulfides (11Fernandes A.P. Holmgren A. Antioxid. Redox Signal. 2004; 6: 63-74Crossref PubMed Scopus (555) Google Scholar, 17Grant C.M. Mol. Microbiol. 2001; 39: 533-541Crossref PubMed Scopus (343) Google Scholar, 18Lillig C.H. Berndt C. Vergnolle O. Lönn M.E. Hudemann C. Bill E. Holmgren A. Proc. Natl. Acad. Sci. U. S. A. 2005; 102: 8168-8173Crossref PubMed Scopus (244) Google the of Grxs has one conserved cysteine residue in the putative active motif, that monothiol Grxs are also conserved prokaryotes and eukaryotes the sequence of those Grxs, we that AtGRXcp is the plant monothiol AtGRXcp a Grxs have a in yeast Grx5 is (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar), and Grx3 to Bellí G. M.T. Herrero E. J. Biol. Chem. 2004; 279: Full Text Full Text PDF PubMed Scopus Google Scholar), whereas a is in the S. M. K. Y. N. A. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar). In to the function of AtGRXcp, we with and this protein in cells. was to to chloroplasts or in cells Analysis of the AtGRXcp sequence that a is the not To we this putative and the AtGRXcp with for expression in cells. in to chloroplasts and was the and to with not AtGRXcp the of a Yeast grx5 to grx5 cells are in and to oxidative stresses (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar). To AtGRXcp Grx5 function and suppress the sensitivity of grx5 cells to an we AtGRXcp, and yeast Grx5 in grx5 cells. yeast in of growth grx5 cells in the with both and grx5 cells in a to cells that AtGRXcp is to suppress the sensitivity of grx5 cells to oxidative that AtGRXcp localized to which are to plants and yeast Grx5 is a mitochondrial Grx (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar), the of grx5 that the of AtGRXcp in yeast cells that in To was in yeast cells. Yeast growth that was functional and suppress the sensitivity of grx5 cells to H2O2 Through localized to mitochondria in yeast cells, whereas a was to to this of AtGRXcp to mitochondria was for the function of this protein in yeast, both and to suppress the sensitivity of grx5 cells to H2O2 and AtGRXcp to against and the of a Yeast grx5 grx5 cells, protein is increased under oxidative that yeast Grx5 a role in protecting oxidative (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar). In to AtGRXcp protein carbonylation in the grx5 cells, we of and grx5 cells in protein in cells was with the cells but to cells demonstrate that AtGRXcp can cells against protein oxidative Yeast Grx5 is a mitochondrial Grx required for the of (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar, U. J. N. R. EMBO J. PubMed Scopus (343) Google Scholar). of Grx5 in of the mitochondrial which is involved in lysine (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar, H. P. K. 2005; PubMed Scopus Google Scholar). work that grx5 cells to (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google of AtGRXcp the lysine auxotrophy of grx5 cells, AtGRXcp was in with grx5 cells that AtGRXcp can partially Grx5 function in yeast cells. AtGRXcp in grx5 in both yeast and that of Grx5 iron-sulfur as a iron which in increased of iron (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar, H. P. K. 2005; PubMed Scopus Google Scholar). iron accumulation in the sensitivity of grx5 cells to such as because of ROS (19Rodrígues-Manzaneque M.T. Ros J. Cabiscol E. Sorribas A. Herrero E. Mol. Cell. Biol. 1999; 19: 8180-8190Crossref PubMed Scopus (267) Google Scholar, M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar). have demonstrated that AtGRXcp yeast cells against oxidative damage and and To the function of AtGRXcp, we the iron in and grx5 cells and in and and cells both to suppress the iron accumulation the cell and and Analysis of the Grxs a conserved putative active motif G. J. Tamarit J. M.T. Ros J. Herrero E. J. Biol. Chem. 2002; Full Text Full Text PDF PubMed Scopus Google Scholar). To the of the for AtGRXcp we two was and was the growth to in the conserved motif AtGRXcp Yeast cells or in in with and grx5 cells not However, under oxidative and grx5 cells grx5 cells, whereas grx5 cells a cells not To and protein expression and we to and the yeast was whereas to AtGRXcp that the protein which in the of to suppress the sensitivity of grx5 cells to can yeast that the in the motif is not for AtGRXcp that in the of be in yeast and plant cells. To we both and in cells. the fluorescent of the and the whereas was in for the and cells that the the protein expression and the of AtGRXcp in both yeast and plant cells. AtGRXcp in and that AtGRXcp is in plants with high of AtGRXcp in green J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). To and AtGRXcp the AtGRXcp was and with the β-glucuronidase and lines that all lines expression not was in the young In addition, was in the green vascular and AtGRXcp for the biological function of AtGRXcp in planta, we two lines and H. P. J. P. R. PubMed Scopus Google a in AtGRXcp To the of the in atgrxcp plants, we used and to and two and of the that in the is in the of AtGRXcp and in atgrxcp the is AtGRXcp expression as and to defects in and early growth in in with that AtGRXcp is to yeast Grx5 function iron accumulation (21Rodríguez-Manzaneque M.T. Tamarit J. Bellí G. Ros J. Herrero E. Mol. Biol. Cell. 2002; 13: 1109-1121Crossref PubMed Scopus (400) Google Scholar), we in an AtGRXcp the iron sensitivity of and atgrxcp and both and was and atgrxcp However, and atgrxcp and and young of atgrxcp a as in growth that AtGRXcp is localized to which are major of ROS we that AtGRXcp in protecting against protein in chloroplasts. To we and plants and of the protein in the protein carbonylation for atgrxcp was higher that for and plants not protein in chloroplasts both photosynthesis and (1Apel K. Hirt H. Annu. Rev. Plant Biol. 2004; 55: 373-399Crossref PubMed Scopus (8734) Google Scholar, B.B. Balmer Y. Annu. Rev. Plant Biol. 2005; 56: 187-220Crossref PubMed Scopus (720) Google Scholar). have a network to ROS (2Vranová E. Inzé D. Van Breusegem F. J. Exp. Bot. 2002; 53: 1227-1236Crossref PubMed Google Scholar, 3Rhoads D.M. Umbach A.L. Chalivendra S.C. Siedow J.N. Plant Physiol. 2006; 141: 357-366Crossref PubMed Scopus (417) Google Scholar, 4Foyer C.H. Noctor G. Plant Cell. 2005; 17: 1866-1875Crossref PubMed Scopus (2217) Google Scholar). that plant Grx are to those in other as we in this functional also the of to AtGRXcp J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). that the characterized plant Grx, AtGRXcp, is a functional monothiol Grx localized to chloroplasts also demonstrate that of AtGRXcp in to protein in chloroplasts and to such as H2O2 and a role of AtGRXcp in redox in chloroplasts. of Grxs have been identified in species In plants, members of this protein are to to and function in 2004; PubMed Scopus (123) Google is physiological plant AtGRXcp and Grx5 are to suppress yeast grx5 H. P. K. 2005; PubMed Scopus Google Scholar), that the biological function of this group of monothiol is Interestingly, localized to the mitochondria in yeast cells AtGRXcp localized to chloroplasts in plant cells of AtGRXcp have been for other plant and yeast Bellí G. M.T. Herrero E. J. Biol. Chem. 2004; 279: Full Text Full Text PDF PubMed Scopus Google Scholar, Plant Cell. 2002; PubMed Scopus Google Scholar). the plant to the in plants but to mitochondria in yeast Plant Cell. 2002; PubMed Scopus Google Scholar). localized yeast Grx3 has been to be to for Grx5 localized to the mitochondria Bellí G. M.T. Herrero E. J. Biol. Chem. 2004; 279: Full Text Full Text PDF PubMed Scopus Google Scholar). of AtGRXcp in yeast is for as the that the of AtGRXcp was the of AtGRXcp was to mitochondria and suppress the sensitivity of grx5 cells to H2O2 of AtGRXcp to partially the and suppress iron accumulation in yeast grx5 cells suggests that AtGRXcp be required for biogenesis of iron-sulfur involved in the of iron in chloroplasts. In plants, have an important role in the and the for J. S. Plant Sci. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). also many such as a and B.B. P. Jacquot J.-P. 2002; PubMed Scopus Google Scholar). that and to sensitivity to oxidative damage E. Olsson O. Nyström T. J. Biol. Chem. 2004; 279: 22204-22208Abstract Full Text Full Text PDF PubMed Scopus (140) Google Scholar). is a that AtGRXcp protein oxidative damage via iron to control oxygen within chloroplasts. for this was in yeast cells. AtGRXcp protein iron and in plants, chloroplasts of atgrxcp plants to increased an of increased oxidative damage to is also that AtGRXcp of yeast grx5 was to of the ROS and In of this that monothiol Grxs can cellular signaling R. Facchin S. Sartori G. Arrigoni G. Casonato S. Ruzzene M. Pinna L.A. Carignani G. Biochem. J. 2004; 377: 395-405Crossref PubMed Scopus (61) Google Scholar, J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar, C. G. N. E. P. C. A. J. P. EMBO J. 2002; PubMed Scopus Google Scholar). work be to the of AtGRXcp and the of ROS in AtGRXcp the putative active motif, and of the conserved cysteine residue with a expression and of AtGRXcp in both yeast and plant cells In of both the conserved and the in yeast Grx5 and the conserved in bacterial Grx4 not protein A.P. Fladvad M. Berndt C. Andrésen C. Lillig C.H. Neubauer P. Sunnerhagen M. Holmgren A. Vlamis-Gardikas A. J. Biol. Chem. 2005; 280: 24544-24552Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar, G. J. Tamarit J. M.T. Ros J. Herrero E. J. Biol. Chem. 2002; Full Text Full Text PDF PubMed Scopus Google Scholar, J. Bellí G. Cabiscol E. Herrero E. Ros J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). that this cysteine residue play a role in the plant In addition, that the conserved residue is not for the function of AtGRXcp In this are to that with the in yeast Grx5 G. J. Tamarit J. M.T. Ros J. Herrero E. J. Biol. Chem. 2002; Full Text Full Text PDF PubMed Scopus Google Scholar). Recently, the of the bacterial Grx4 that this monothiol Grx has a which is the dithiol Grxs M. M. A.P. S. Vlamis-Gardikas A. Holmgren A. Sunnerhagen M. J. Biol. Chem. 2005; 280: Full Text Full Text PDF PubMed Scopus Google Scholar). AtGRXcp of cysteine the conserved and the which are in the conserved and two cysteine and that are not conserved in the monothiol Grxs J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (61) Google Scholar). work to be the roles cysteine have in disulfide and have to the of that AtGRXcp, yeast Grx5 and bacterial Grx4, was not active in the or the disulfide not A.P. Fladvad M. Berndt C. Andrésen C. Lillig C.H. Neubauer P. Sunnerhagen M. Holmgren A. Vlamis-Gardikas A. J. Biol. Chem. 2005; 280: 24544-24552Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar, J. Bellí G. Cabiscol E. Herrero E. Ros J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). AtGRXcp a of roles in other AtGRXcp have that has high of protein during growth E. Olsson O. Nyström T. J. Biol. Chem. 2004; 279: 22204-22208Abstract Full Text Full Text PDF PubMed Scopus (140) Google Scholar, C. L. Y. M. D. Plant Physiol. 2005; PubMed Scopus Google Scholar). AtGRXcp is in young cotyledons, green and the of that AtGRXcp be for protecting against oxidative damage during early growth and In with atgrxcp are to is that AtGRXcp be involved in the of with and in which is required for early seedling growth K. Antioxid. Redox Signal. 2005; PubMed Scopus Google Scholar). is that in redox via have an important role in cell and plant K. T. S. H. M. K. Plant Cell Physiol. 2005; PubMed Scopus Google Scholar, M. M. M. K. Plant Cell Physiol. 2004; PubMed Scopus Google Scholar). In addition, a Grx, to play a role in of that are required for S. S. 2005; PubMed Scopus Google Scholar). atgrxcp plants not sensitivity to iron the plant not this be to of iron G. N. F. F. C. Plant Cell. 2002; PubMed Scopus Google or functional Grxs N. Gelhaye E. Jacquot J.-P. Cell Mol. Life. Sci. 2004; 61: 1266-1277Crossref PubMed Scopus (182) Google Scholar, 2004; PubMed Scopus (123) Google Scholar). Grxs and antioxidant also be in characterization of AtGRXcp is in that Grxs have not been previously characterized. AtGRXcp to be conserved and the of AtGRXcp to rescue yeast Grx5 suggests a conserved mechanism monothiol plant lines demonstrate that this protein a role in protecting protein during that are in the the characterization of AtGRXcp is an important this in plants to stresses. Herrero for and yeast for the for for and and for of the