title: The circularly permuted yellow fluorescent protein cpYFP that has been used as a superoxide probe is highly responsive to pH but not superoxide in mitochondria: implications for the existence of superoxide 'flashes'.
abstract: The properties of a cpYFP [circularly permuted YFP (yellow fluorescent protein)] reported to act as a superoxide sensor have been re-examined in Arabidopsis mitochondria. We have found that the probe has high pH sensitivity and that dynamics in the cpYFP signal disappeared when the matrix pH was clamped by nigericin. In contrast, genetic and pharmacological manipulation of matrix superoxide had no detectable effect on the cpYFP signal. These findings question the existence of superoxide flashes in mitochondria.
authors.affiliation: Department of Plant Science, University of Oxford, South Parks Road, Oxford OX1 3RB, UK. markus.schwarzlander@plants.ox.ac.uk
authors.forename: Markus
authors.initials: M
authors.lastname: Schwarzländer
authors.forename: David C
authors.initials: DC
authors.lastname: Logan
authors.forename: Mark D
authors.initials: MD
authors.lastname: Fricker
authors.forename: Lee J
authors.initials: LJ
authors.lastname: Sweetlove
mesh_terms: D017360:Arabidopsis / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008164:Luminescent Proteins / Q000737:chemistry / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D010101:Oxygen Consumption; D019441:Plant Epidermis / Q000166:cytology / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology; D013481:Superoxides / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D008164:Luminescent Proteins; C054562:yellow fluorescent protein, Bacteria; D013481:Superoxides