title: Mitochondria and copper homeostasis in plants.
abstract: Copper (Cu) and other transition metals are essential for living organisms but also toxic when present in excess. To cope with this apparent paradox, organisms have developed sophisticated mechanisms to acquire, transport and store these metals. Particularly, plant mitochondria require Cu for the assembly and function of cytochrome c oxidase (COX), the terminal enzyme of the respiratory chain. COX assembly is a complex process that requires the action of multiple factors, many of them involved in the delivery and insertion of Cu into the enzyme. In this review, we summarize what is known about the processes involved in Cu delivery to mitochondria and how these processes impact in Cu homeostasis at the cellular level. We also discuss evidence indicating that metallochaperones involved in COX assembly play additional roles in signaling pathways related to changes in Cu and redox homeostasis and the response of plants to stress. We propose that cysteine-rich proteins present in the mitochondrial intermembrane space are excellent candidates as sensors of these changes and transducers of signals originated in the organelle to the rest of the cell.
authors.affiliation: Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CC 242 Paraje El Pozo, 3000 Santa Fe, Argentina.
authors.forename: Lucila
authors.initials: L
authors.lastname: Garcia
authors.affiliation: Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CC 242 Paraje El Pozo, 3000 Santa Fe, Argentina.
authors.forename: Elina
authors.initials: E
authors.lastname: Welchen
authors.affiliation: Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CC 242 Paraje El Pozo, 3000 Santa Fe, Argentina. Electronic address: dhgonza@fbcb.unl.edu.ar.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Gonzalez
mesh_terms: D003300:Copper / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism; D006706:Homeostasis; D008928:Mitochondria / Q000378:metabolism*; D051336:Mitochondrial Membranes / Q000201:enzymology; D010944:Plants / Q000201:enzymology / Q000378:metabolism*; D055503:Protein Multimerization
chemical_list: D003300:Copper; D003576:Electron Transport Complex IV
keywords: Assembly factor; Copper; Cytochrome c oxidase; Metallochaperone; Mitochondrion