Glutaredoxin GRXS17 Associates with the Cytosolic Iron-Sulfur Cluster Assembly Pathway

Sabrina Iñigo; Astrid Nagels Durand; Andrés Ritter; Sabine Le Gall; Martin Termathe; Roland Klassen; Takayuki Tohge; Barbara De Coninck; Jelle Van Leene; Rebecca De Clercq; Bruno P A Cammue; Alisdair R Fernie; Kris Gevaert; Geert De Jaeger; Sebastian A Leidel; Raffael Schaffrath; Mieke Van Lijsebettens; Laurens Pauwels; Alain Goossens

doi:10.1104/pp.16.00261

Glutaredoxin GRXS17 Associates with the Cytosolic Iron-Sulfur Cluster Assembly Pathway

Plant Physiol. 2016 Oct;172(2):858-873. doi: 10.1104/pp.16.00261. Epub 2016 Aug 8.

Authors

Sabrina Iñigo¹, Astrid Nagels Durand¹, Andrés Ritter¹, Sabine Le Gall¹, Martin Termathe¹, Roland Klassen¹, Takayuki Tohge¹, Barbara De Coninck¹, Jelle Van Leene¹, Rebecca De Clercq¹, Bruno P A Cammue¹, Alisdair R Fernie¹, Kris Gevaert¹, Geert De Jaeger¹, Sebastian A Leidel¹, Raffael Schaffrath¹, Mieke Van Lijsebettens¹, Laurens Pauwels¹, Alain Goossens²

Affiliations

¹ Department of Plant Systems Biology, VIB, B-9052 Ghent, Belgium (S.I., A.N.D., A.R., S.L.G., B.D.C., J.V.L., R.D.C., B.P.A.C., G.D.J., M.V.L., L.P., A.G.);Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium (S.I., A.N.D., A.R., S.L.G., J.V.L., R.D.C., G.D.J., M.V.L., L.P., A.G.);Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Muenster, Germany (M.T., S.A.L.);Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, D-34132 Kassel, Germany (R.K., R.S.);Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany (T.T., A.R.F.);Centre of Microbial and Plant Genetics, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium (B.D.C., B.P.A.C.);Cells-in-Motion Cluster of Excellence (M.T., S.A.L.) and Faculty of Medicine (S.A.L.), University of Muenster, 48149 Muenster, Germany;Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium (K.G.); andDepartment of Biochemistry, Ghent University, B-9000 Ghent, Belgium (K.G.).
² Department of Plant Systems Biology, VIB, B-9052 Ghent, Belgium (S.I., A.N.D., A.R., S.L.G., B.D.C., J.V.L., R.D.C., B.P.A.C., G.D.J., M.V.L., L.P., A.G.);Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium (S.I., A.N.D., A.R., S.L.G., J.V.L., R.D.C., G.D.J., M.V.L., L.P., A.G.);Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Muenster, Germany (M.T., S.A.L.);Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, D-34132 Kassel, Germany (R.K., R.S.);Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany (T.T., A.R.F.);Centre of Microbial and Plant Genetics, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium (B.D.C., B.P.A.C.);Cells-in-Motion Cluster of Excellence (M.T., S.A.L.) and Faculty of Medicine (S.A.L.), University of Muenster, 48149 Muenster, Germany;Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium (K.G.); andDepartment of Biochemistry, Ghent University, B-9000 Ghent, Belgium (K.G.) alain.goossens@psb.vib-ugent.be.

Abstract

Cytosolic monothiol glutaredoxins (GRXs) are required in iron-sulfur (Fe-S) cluster delivery and iron sensing in yeast and mammals. In plants, it is unclear whether they have similar functions. Arabidopsis (Arabidopsis thaliana) has a sole class II cytosolic monothiol GRX encoded by GRXS17 Here, we used tandem affinity purification to establish that Arabidopsis GRXS17 associates with most known cytosolic Fe-S assembly (CIA) components. Similar to mutant plants with defective CIA components, grxs17 loss-of-function mutants showed some degree of hypersensitivity to DNA damage and elevated expression of DNA damage marker genes. We also found that several putative Fe-S client proteins directly bind to GRXS17, such as XANTHINE DEHYDROGENASE1 (XDH1), involved in the purine salvage pathway, and CYTOSOLIC THIOURIDYLASE SUBUNIT1 and CYTOSOLIC THIOURIDYLASE SUBUNIT2, both essential for the 2-thiolation step of 5-methoxycarbonylmethyl-2-thiouridine (mcm⁵s²U) modification of tRNAs. Correspondingly, profiling of the grxs17-1 mutant pointed to a perturbed flux through the purine degradation pathway and revealed that it phenocopied mutants in the elongator subunit ELO3, essential for the mcm⁵ tRNA modification step, although we did not find XDH1 activity or tRNA thiolation to be markedly reduced in the grxs17-1 mutant. Taken together, our data suggest that plant cytosolic monothiol GRXs associate with the CIA complex, as in other eukaryotes, and contribute to, but are not essential for, the correct functioning of client Fe-S proteins in unchallenged conditions.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Arabidopsis / genetics
Arabidopsis / metabolism
Arabidopsis Proteins / genetics
Arabidopsis Proteins / metabolism*
Biosynthetic Pathways*
Cytosol / metabolism*
DNA Damage
Gene Expression Regulation, Plant
Glutaredoxins / genetics
Glutaredoxins / metabolism*
Immunoblotting
Iron-Sulfur Proteins / metabolism*
Mutation
Plant Leaves / genetics
Plant Leaves / metabolism
Plant Roots / genetics
Plant Roots / metabolism
Plants, Genetically Modified
Protein Binding
Reverse Transcriptase Polymerase Chain Reaction
Xanthine Dehydrogenase / genetics
Xanthine Dehydrogenase / metabolism

Substances

Arabidopsis Proteins
GRXS17 protein, Arabidopsis
Glutaredoxins
Iron-Sulfur Proteins
Xanthine Dehydrogenase