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Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
RESEARCH ARTICLE

Regulation of the chloroplastic copper chaperone (CCS) and cuprozinc superoxide dismutase (CSD2) by alternative splicing and copper excess in Glycine max

Sara Sagasti A , María Bernal A , Diana Sancho A , Miren B. del Castillo A and Rafael Picorel A B
+ Author Affiliations
- Author Affiliations

A Department of Plant Nutrition, Estación Experimental de Aula Dei (EEAD), Consejo Superior de Investigaciones Científicas (CSIC), Carretera Montañana 1005, 50059 Zaragoza, Spain.

B Corresponding author. Email: picorel@eead.csic.es

Functional Plant Biology 41(2) 144-155 https://doi.org/10.1071/FP13134
Submitted: 8 May 2013  Accepted: 30 July 2013   Published: 18 September 2013

Abstract

Metal homeostasis is an important aspect of plant physiology, and the copper transport into the chloroplast and its fate after delivery is of special relevance for plants. In this work, the regulation of the chloroplastic copper chaperone for the cuprozinc superoxide dismutase (GmCCS) and its target, the cuprozinc superoxide dismutase (GmCSD2), was investigated in photosynthetic cell suspensions and entire plants from Glycine max (L.) Merr. Both genes were expressed in cell suspensions and in all plant tissues analysed, and their RNAs matured by alternative splicing with intron retention (IntronR). This mechanism generated a spliced and three non-spliced mRNAs in the case of GmCCS but only a spliced and a non-spliced mRNAs in GmCSD2. Copper excess strongly upregulated the expression of both fully spliced mRNAs but mostly unaffected the non-spliced forms. In entire plants, some tissue specificity was also observed depending on copper content status. At the protein level, the GmCCS was mostly unaffected but the GmCSD2 was strongly induced under copper excess in all subcellular fractions analysed, suggesting a post-transcriptional regulation for the former. This different protein regulation of the chaperone and its target may indicate some additional function for the CSD2 protein. In addition to its well-known superoxide dismutase (SOD) activity, it may also function as a metal sink in copper excess availability to avoid metal cell damage. Furthermore, the GmCCS seems to be present in the stroma only but the GmCSD2 was present in both stroma and thylakoids despite the general idea that the SOD enzymes are typically soluble stroma proteins. The presence of the SOD enzyme on the surface of the thylakoid membranes is reasonable considering that the superoxide radical (O2) is preferentially formed at the acceptor side of the PSI.

Additional keywords: cell suspensions, gene, homeostasis, hydroponic, protein.


References

Abdel-Ghany SE, Pilon M (2008) MicroRNA-mediated systemic down-regulation of copper protein expression in response to low copper availability in Arabidopsis. Journal of Biological Chemistry 283, 15 932–15 945.
MicroRNA-mediated systemic down-regulation of copper protein expression in response to low copper availability in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXmsFert7k%3D&md5=807daed1938f270bd126a0489048caccCAS |

Abdel-Ghany SE, Burkhead JL, Gogolin KA, Andres-Colas N, Bodecker JR, Puig S, Peñarrubia L, Pilon M (2005a) AtCCS is a functional homolog of the yeast copper chaperone CCS1/Lys7. FEBS Letters 579, 2307–2312.
AtCCS is a functional homolog of the yeast copper chaperone CCS1/Lys7.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXjsVGkt7w%3D&md5=53d6e5e5301db67fe9c79abd709bd8b8CAS | 15848163PubMed |

Abdel-Ghany SE, Müller-Moulé P, Niyogi KK, Pilon M, Shikanai T (2005b) Two P-type ATPases are required for copper delivery in Arabidopsis thaliana chloroplasts. The Plant Cell 17, 1233–1251.
Two P-type ATPases are required for copper delivery in Arabidopsis thaliana chloroplasts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXjslSgsrY%3D&md5=f3536984f636c496ab0e9b68953b5eefCAS | 15772282PubMed |

Andreasson E, Svensson P, Weibull C, Albertsson P-A (1988) Separation and characterization of stroma and grana membranes – evidence for heterogeneity in antenna size of both photosystem I and photosystem II. Biochimica et Biophysica Acta 936, 339–350.
Separation and characterization of stroma and grana membranes – evidence for heterogeneity in antenna size of both photosystem I and photosystem II.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXlsVKhsQ%3D%3D&md5=87c94f0368a4fae32be53b61d2ea61deCAS |

Arnon DI (1950) Dennis Robert Hoagland: 1884–1949. Science 112, 739–742.
Dennis Robert Hoagland: 1884–1949.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaG3M%2Fislyrtw%3D%3D&md5=6f45dea4759f0f27b92a24598bc30fefCAS | 14798335PubMed |

Asada K (1999) The water-water cycle in chloroplasts: scavenging of active oxygens and dissipation of excess photons. Annual Review of Plant Physiology and Plant Molecular Biology 50, 601–639.
The water-water cycle in chloroplasts: scavenging of active oxygens and dissipation of excess photons.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXkt1yktr0%3D&md5=42c7bb092be417953e2e6cb785574401CAS | 15012221PubMed |

Beauchamp CH, Fridovich I (1971) Superoxide dismutase improved assays and an assay applicable to acrylamide gels. Analytical Biochemistry 44, 276–287.
Superoxide dismutase improved assays and an assay applicable to acrylamide gels.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE38XjtFKhsg%3D%3D&md5=147919b59eca1535af9ba4ac13578c47CAS |

Beauclair L, Agnès Y, Bouché N (2010) microRNA-directed cleavage and translational repression of the copper chaperone for superoxide dismutase mRNA in Arabidopsis. The Plant Journal 62, 454–462.
microRNA-directed cleavage and translational repression of the copper chaperone for superoxide dismutase mRNA in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXmtFygsLo%3D&md5=f33a318b3e7e34baec3926110deb396cCAS | 20128885PubMed |

Bernal M, Ramiro MV, Cases R, Picorel R, Yruela I (2006) Excess copper effect on growth, chloroplast ultrastructure, oxygen-evolution activity and chlorophyll fluorescence in Glycine max cell suspensions. Physiologia Plantarum 127, 312–325.
Excess copper effect on growth, chloroplast ultrastructure, oxygen-evolution activity and chlorophyll fluorescence in Glycine max cell suspensions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XmtFSrsrk%3D&md5=1a61eee5577a61cf0289da8b8f3b068dCAS |

Bradford M (1976) A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of dye binding. Analytical Biochemistry 72, 248–254.
A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of dye binding.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE28XksVehtrY%3D&md5=bead43c1adb6f57157bea3eab849e63cCAS | 942051PubMed |

Burge C, Karlin S (1997) Prediction of complete gene structures in human genomic DNA. Journal of Molecular Biology 268, 78–94.
Prediction of complete gene structures in human genomic DNA.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjtlSqtL4%3D&md5=fa962b321fa30d78fb3a213dd85ac2d7CAS | 9149143PubMed |

Burkhead JL, Abdel-Ghany SE, Morrill JM, Pilon-Smits EA, Pilon M (2003) The Arabidopsis thaliana CUTA gene encodes an evolutionarily conserved copper binding chloroplast protein. The Plant Journal 34, 856–867.
The Arabidopsis thaliana CUTA gene encodes an evolutionarily conserved copper binding chloroplast protein.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXlvFajsb0%3D&md5=14b2707edcde6dd67a0d5de1c1076b2bCAS | 12795705PubMed |

Burkhead JL, Reynolds KA, Abdel-Ghany SE, Cohu CM, Pilon M (2009) Copper homeostasis. New Phytologist 182, 799–816.
Copper homeostasis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmvVOgt7g%3D&md5=2043ffbedfaf6ac95881eec57b610a3dCAS | 19402880PubMed |

Chu CC, Lee WC, Guo WY, Pan SM, Chen LJ, Li HM, Jinn TL (2005) A copper chaperone for superoxide dismutase that confers three types of copper/zinc superoxide dismutase activity in Arabidopsis. Plant Physiology 139, 425–436.
A copper chaperone for superoxide dismutase that confers three types of copper/zinc superoxide dismutase activity in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtVCgurrO&md5=7548368d9d72a84be4ec1a0194d181ccCAS | 16126858PubMed |

Cohu CM, Pilon M (2007) Regulation of superoxide dismutase expression by copper availability. Physiologia Plantarum 129, 747–755.
Regulation of superoxide dismutase expression by copper availability.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXksVOisbo%3D&md5=937fc8daf3297d1ca968ed58c961fcc7CAS |

Cohu CM, Abdel-Ghany SE, Reynolds KAG, Onofrio AM, Bodecker JR, Kimbrel JA, Niyogi KK, Pilon M (2009) Copper delivery by the copper chaperone for chloroplast and cytosolic copper/zinc-superoxide dismutases: regulation and unexpected phenotypes in an Arabidopsis mutant. Molecular Plant 2, 1336–1350.
Copper delivery by the copper chaperone for chloroplast and cytosolic copper/zinc-superoxide dismutases: regulation and unexpected phenotypes in an Arabidopsis mutant.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsV2itLzO&md5=c8d7a28c8963f7ce02934c6fd29a7224CAS | 19969519PubMed |

Culotta VC, Joh HD, Lin SJ, Slekar KH, Strain J (1995) A physiological role for Saccharomyces cerevisiae copper/zinc superoxide dismutase in copper buffering. Journal of Biological Chemistry 270, 29 991–29 997.
A physiological role for Saccharomyces cerevisiae copper/zinc superoxide dismutase in copper buffering.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXhtVSitbnO&md5=79d7cc5792dbe54c743466f4cbfa0364CAS |

Culotta VC, Klomp LWJ, Strain J, Casareno RLB, Krems B, Gitlin J (1997) The copper chaperone for superoxide dismutase. Journal of Biological Chemistry 272, 23 469–23 472.
The copper chaperone for superoxide dismutase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmtlOhs7o%3D&md5=9e987ec722f79d4170bba7d2ca4b8c6cCAS |

del Pozo T, Cambiazo V, Gonzalez M (2010) Gene expression profiling analysis of copper homeostasis in Arabidopsis thaliana. Biochemical and Biophysical Research Communications 393, 248–252.
Gene expression profiling analysis of copper homeostasis in Arabidopsis thaliana.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjtVCltbY%3D&md5=29a8616c91755f4f39cb75466739950cCAS | 20117084PubMed |

Dugas DV, Bartel B (2008) Sucrose induction of Arabidopsis miR398 represses two Cu/Zn superoxide dismutases. Plant Molecular Biology 67, 403–417.
Sucrose induction of Arabidopsis miR398 represses two Cu/Zn superoxide dismutases.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXmslOmur8%3D&md5=236366a60365a324b613c6741698aec4CAS | 18392778PubMed |

Halliwell B, Gutteridge JMC (1984) Oxygen toxicity, oxygen radicals, transition metals and disease. Biochemical Journal 219, 1–14.

Himelblau E, Amasino RM (2000) Delivering copper within plant cells. Current Opinion in Plant Biology 3, 205–210.

Huang CH, Kuo WY, Weiss C, Jinn TL (2012) Copper chaperone-dependent and -independent activation of three copper-zinc superoxide dismutase homologs localized in different cellular compartments in Arabidopsis. Plant Physiology 158, 737–746.
Copper chaperone-dependent and -independent activation of three copper-zinc superoxide dismutase homologs localized in different cellular compartments in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XltVOktLo%3D&md5=cc015c8357e3b2974bf6d4508ebbcfadCAS | 22186608PubMed |

Itoh H, Washio T, Tomita M (2004) Computational comparative analyses of alternative splicing regulation using full-length cDNA of various eukaryotes. RNA 10, 1005–1018.
Computational comparative analyses of alternative splicing regulation using full-length cDNA of various eukaryotes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXltlKmuro%3D&md5=eaa1816dd7c5a2569eaea0c8a2042125CAS | 15208437PubMed |

Kazan K (2003) Splicing and proteome diversity in plants: the tip of iceberg has just emerged. Trends in Plant Science 8, 468–471.
Splicing and proteome diversity in plants: the tip of iceberg has just emerged.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXnvFShsr8%3D&md5=910eda850873377f1972617f92238b49CAS | 14557042PubMed |

Kliebenstein DJ, Monde R-A, Last RL (1998) Superoxide dismutase in Arabidopsis: an eclectic enzyme family with disparate regulation and protein localization. Plant Physiology 118, 637–650.
Superoxide dismutase in Arabidopsis: an eclectic enzyme family with disparate regulation and protein localization.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXmslyqtb0%3D&md5=b6483a2759ca8cd18e80b1bdf839bf44CAS | 9765550PubMed |

Laemmli UK (1970) Cleavage of structural proteins during the assembly of the head of bacteriophage. Nature 227, 680–685.
Cleavage of structural proteins during the assembly of the head of bacteriophage.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlsFags7s%3D&md5=445d75904529d747c279af05b4e6db88CAS | 5432063PubMed |

Lamb AL, Wernimont AK, Pufahl RA, Culotta VC, O’Halloran TV, Rosenzweig AC (1999) Crystal structure of the copper chaperone for superoxide dismutase. Nature Structural Biology 6, 724–729.
Crystal structure of the copper chaperone for superoxide dismutase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXltVSitb4%3D&md5=ccea2587c68d81376cf045acec70b91bCAS | 10426947PubMed |

Lamb AL, Wernimont AK, Pufahl RA, O’Halloran TV, Rosenzweig AC (2000) Crystal structure of the second domain of the human copper chaperone for superoxide dismutase. Biochemistry 39, 1589–1595.
Crystal structure of the second domain of the human copper chaperone for superoxide dismutase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXms1WhtA%3D%3D&md5=8126f402c9090ee36e0bab184044c804CAS | 10677207PubMed |

Mauro S, Van Eycken F, Challou N, Lucas P, L’Oiseau M (2005) Characterization of new maize chloroplastic copper/zinc superoxide dismutase isoforms by high resolution native two-dimensional polyacrylamide gel electrophoresis. Identification of chilling responsive chloroplastic superoxide dismutase isoforms. Physiologia Plantarum 124, 323–335.
Characterization of new maize chloroplastic copper/zinc superoxide dismutase isoforms by high resolution native two-dimensional polyacrylamide gel electrophoresis. Identification of chilling responsive chloroplastic superoxide dismutase isoforms.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXlvFGisbg%3D&md5=03b321786e8bd76f9b42ae72d4e506ddCAS |

Ogawa K, Kanematsu S, Takabe K, Asada K (1995) Attachment of CuZn-superoxide dismutase to thylakoid membranes at the site of superoxide generation (PSI) in spinach chloroplasts: detection by immunogold labeling after rapid freezing and substitution method. Plant & Cell Physiology 36, 565–573.

Pilon M, Abdel-Ghany SE, Cohu CM, Gogolin KA, Ye H (2006) Copper cofactor delivery in plant cells. Current Opinion in Plant Biology 9, 256–263.
Copper cofactor delivery in plant cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XktVGgtbs%3D&md5=8c47a3157d632129b07edf9c1db5284cCAS | 16616609PubMed |

Pilon M, Ravet K, Tapken W (2011) The biogenesis and physiological function of chloroplast superoxide dismutases. Biochimica et Biophysica Acta 1807, 989–998.
The biogenesis and physiological function of chloroplast superoxide dismutases.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXntVyltrY%3D&md5=667a0961db596460b2c71104cbaab71fCAS | 21078292PubMed |

Redinbo MR, Yeates TO, Merchant S (1994) Plastocyanin: structural and functional analysis. Journal of Bioenergetics and Biomembranes 26, 49–66.
Plastocyanin: structural and functional analysis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXksFamsbc%3D&md5=39eb140895f7ab79ab2943de23e598a4CAS | 8027022PubMed |

Rogers SMD, Ogren WL, Widholm JM (1987) Photosynthetic characteristics of a photoautotrophic cell suspension culture of soybean. Plant Physiology 84, 1451–1456.
Photosynthetic characteristics of a photoautotrophic cell suspension culture of soybean.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXltlWitbs%3D&md5=9c62b95a6e2e09e6382a19b24ad544c3CAS |

Ruzsa SM, Scandalios JG (2003) Altered Cu metabolism and differential transcription of Cu/ZnSod genes in a Cu/ZnSOD-deficient mutant of maize: evidence for a Cu-responsive transcription factor. Biochemistry 42, 1508–1516.
Altered Cu metabolism and differential transcription of Cu/ZnSod genes in a Cu/ZnSOD-deficient mutant of maize: evidence for a Cu-responsive transcription factor.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXkvFKhtw%3D%3D&md5=146e8c558c2fc9d2280a1314cedfec84CAS | 12578363PubMed |

Sagasti S (2009) PhD Thesis, Department of Biochemistry and Molecular and Cell Biology, University of Zaragoza, Zaragoza, Spain.

Sagasti S, Yruela I, Bernal M, Lujan MA, Frago S, Medina M, Picorel R (2011) Characterization of the recombinant copper chaperone (CCS) from the plant Glycine (G.) max. Metallomics 3, 169–175.
Characterization of the recombinant copper chaperone (CCS) from the plant Glycine (G.) max.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXjtVWltbY%3D&md5=ba9a795ffe126a577e07db77ce7a3a9eCAS | 21264427PubMed |

Sancenon V, Puig S, Mateu-Andres I, Dorcey E, Thiele DJ, Peñarrubia L (2004) The Arabidopsis copper transporter COPT1 functions in root elongation and pollen development. Journal of Biological Chemistry 279, 15 348–15 355.
The Arabidopsis copper transporter COPT1 functions in root elongation and pollen development.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXivVKgsbo%3D&md5=e2eb4e85bbf2e6b590c1745def829befCAS |

Sandmann G, Böger P (1980) Copper-mediated lipid peroxidation processes in photosynthetic membranes. Plant Physiology 66, 797–800.
Copper-mediated lipid peroxidation processes in photosynthetic membranes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL3MXht12ntw%3D%3D&md5=309c4ab8b4459bc32c28031618b8d8c4CAS | 16661528PubMed |

Schmidt PJ, Rae TD, Pufahl RA, Hamma T, Strain J, O’Halloran TV, Culotta VC (1999a) Multiple protein domains contribute to the action of the copper chaperone for superoxide dismutase. Journal of Biological Chemistry 274, 23 719–23 725.
Multiple protein domains contribute to the action of the copper chaperone for superoxide dismutase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXlsVOns7k%3D&md5=221138e3ba55605828df0ec1b29adf62CAS |

Schmidt PJ, Ramos-Gomez M, Culotta VC (1999b) A gain of superoxide dismutase (SOD) activity obtained with CCS, the copper metallochaperone for SOD1. Journal of Biological Chemistry 274, 36 952–36 956.
A gain of superoxide dismutase (SOD) activity obtained with CCS, the copper metallochaperone for SOD1.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXpsVOq&md5=53fdd24bea023ba43831cd5a5edc277dCAS |

Stasser JP, Eisses JF, Barry AN, Kaplan JH, Blackburn NJ (2005) Cysteine-to-serine mutants of the human copper chaperone for superoxide dismutase reveal a copper cluster at a domain III dimer interface. Biochemistry 44, 3143–3152.
Cysteine-to-serine mutants of the human copper chaperone for superoxide dismutase reveal a copper cluster at a domain III dimer interface.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtF2jsLs%3D&md5=8c89ab74989ee8a6552aba52cb4d29ecCAS | 15736924PubMed |

Stasser JP, Siluvai GS, Barry AN, Blackburn NJ (2007) A multinuclear copper(I) cluster forms the dimerization interface in copper-loaded human copper chaperone for superoxide dismutase. Biochemistry 46, 11 845–11 856.
A multinuclear copper(I) cluster forms the dimerization interface in copper-loaded human copper chaperone for superoxide dismutase.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhtFSjt7fJ&md5=9b811c29316ec29260aca329cc56044eCAS |

Sunkar R, Kapoor A, Zhu JK (2006) Posttranscriptional induction of two Cu/Zn superoxide dismutase genes in Arabidopsis is mediated by downregulation of miR398 and important for oxidative stress tolerance. The Plant Cell 18, 2051–2065.
Posttranscriptional induction of two Cu/Zn superoxide dismutase genes in Arabidopsis is mediated by downregulation of miR398 and important for oxidative stress tolerance.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xos1KjtLY%3D&md5=012eca9f422b8c7bf1d5b53ece5a10cdCAS | 16861386PubMed |

Tapken W, Ravet K, Pilon M (2012) Plastocyanin controls the stabilization of the thylakoid Cu-transporting P-type ATPase PAA2/HMA8 in response to low copper in Arabidopsis. Journal of Biological Chemistry 287, 18 544–18 550.
Plastocyanin controls the stabilization of the thylakoid Cu-transporting P-type ATPase PAA2/HMA8 in response to low copper in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XnsF2nu78%3D&md5=8b706b7bad36f300bb8ec0c982309486CAS |

Thompson JD, Higgins DJ, Gibson TJ (1994) CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Research 22, 4673–4680.
CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXitlSgu74%3D&md5=c03a15a244b2f1b8f1d344a5ce57d164CAS | 7984417PubMed |

Trindade LM, Horvath BM, Bergervoet MJE, Visser RGF (2003) Isolation of a gene encoding a copper chaperone for the copper/zinc superoxide dismutase and characterization of its promoter in potato. Plant Physiology 133, 618–629.
Isolation of a gene encoding a copper chaperone for the copper/zinc superoxide dismutase and characterization of its promoter in potato.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXosVaqt7c%3D&md5=dc10c7eaacc963cf80d7eea2f9d30f5eCAS | 12972661PubMed |

van Wijk KJ, Bingsmark S, Aro EM, Andersson B (1995) In vitro synthesis and assembly of photosystem II core proteins. The D1 protein can be incorporated into photosystem II in isolated chloroplasts and thylakoids. Journal of Biological Chemistry 270, 25 685–25 695.
In vitro synthesis and assembly of photosystem II core proteins. The D1 protein can be incorporated into photosystem II in isolated chloroplasts and thylakoids.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXovFyksrs%3D&md5=90687617802a26f99530b8494a333608CAS |

Wang BB, Brendel V (2006) Genomewide comparative analysis of alternative splicing in plants. Proceedings of the National Academy of Sciences of the United States of America 103, 7175–7180.
Genomewide comparative analysis of alternative splicing in plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xkslykuro%3D&md5=e39c9f4b715ec6168723017adcd16402CAS | 16632598PubMed |

Wintz H, Vulpe C (2002) Plant copper chaperones. Biochemical Society Transactions 30, 732–735.
Plant copper chaperones.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XntVemtLw%3D&md5=94963db8926381cba3ecb49f59ae5e08CAS | 12196180PubMed |

Yamasaki H, Abdel-Ghany SE, Cohu CM, Kobayashi Y, Shikanai T, Pilon M (2007) Regulation of copper homeostasis by microRNA in Arabidopsis. Journal of Biological Chemistry 282, 16 369–16 378.
Regulation of copper homeostasis by microRNA in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXlvVajt7c%3D&md5=acd7317136fd470bff86c0769b94acc5CAS |

Yamasaki H, Hayashi M, Fukazawa M, Kobayashi Y, Shikanai T (2009) SQUAMOSA promoter binding protein-like7 is a central regulator for copper homeostasis in Arabidopsis. The Plant Cell 21, 347–361.
SQUAMOSA promoter binding protein-like7 is a central regulator for copper homeostasis in Arabidopsis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXlsFCitLw%3D&md5=18a732fee6353ca58eacf40073c2acd7CAS | 19122104PubMed |

Yruela I, Alfonso M, Ortiz de Zarate I, Montoya G, Picorel R (1993) Precise location of the Cu(II)-inhibitory binding site in higher plant and bacterial photosynthetic reaction center as probed by light-induced absorption changes. Journal of Biological Chemistry 268, 1684–1689.

Zhu HN, Shipp E, Sanchez RJ, Liba A, Stine JE, Hart PJ, Gralla EB, Nersissian AM, Valentine JS (2000) Cobalt(2+) binding to human and tomato copper chaperone for superoxide dismutase: Implications for the metal ion transfer mechanism. Biochemistry 39, 5413–5421.
Cobalt(2+) binding to human and tomato copper chaperone for superoxide dismutase: Implications for the metal ion transfer mechanism.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXit1yjsrs%3D&md5=f3dd80a091b31c86198ec3ac79e5ff54CAS |