title: Synechocystis mutants defective in manganese uptake regulatory system, ManSR, are hypersensitive to strong light.
abstract: High affinity transport of manganese ions (Mn2+) in cyanobacteria is carried by an ABC-type transporter, encoded by the mntCAB operon, which is derepressed by the deficiency of Mn2+. Transcription of this operon is negatively regulated by the two-component system consisting of a sensory histidine kinase ManS and DNA-binding response regulator ManR. In this study, we examined two Synechocystis mutants, defective in ManS and ManR. These mutants were unable to grow on high concentrations of manganese. Furthermore, they were sensitive to high light intensity and unable to recover after short-term photoinhibition. Under standard illumination and Mn2+concentration, mutant cells revealed the elevated levels of transcripts of genes involved in the formation of Photosystem II (psbA, psbD, psbC, pap-operon). This finding suggests that, in mutant cells, the PSII is sensitive to high concentrations of Mn2+even at relatively low light intensity.
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
authors.forename: Anna
authors.initials: A
authors.lastname: Zorina
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Sinetova
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
authors.forename: Elena V
authors.initials: EV
authors.lastname: Kupriyanova
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
authors.forename: Kirill S
authors.initials: KS
authors.lastname: Mironov
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
authors.forename: Irina
authors.initials: I
authors.lastname: Molkova
authors.affiliation: Moscow City Teacher Training University, 2nd Agricultural Passage 4, Moscow, Russia, 129226.
authors.forename: Lyudmila V
authors.initials: LV
authors.lastname: Nazarenko
authors.affiliation: Department of Genetics, Faculty of Biology, Moscow State University, Moscow, Russia.
authors.forename: Vladislav V
authors.initials: VV
authors.lastname: Zinchenko
authors.affiliation: Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276. losda@ippras.ru.
authors.forename: Dmitry A
authors.initials: DA
authors.lastname: Los
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000502:physiology*; D008345:Manganese / Q000378:metabolism*; D009154:Mutation; D045332:Photosystem II Protein Complex / Q000502:physiology / Q000528:radiation effects; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D046939:Synechocystis / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects
chemical_list: D018528:ATP-Binding Cassette Transporters; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D008345:Manganese
keywords: Cyanobacteria; Ions; Manganese; Sensors; Stress; Synechocystis; Transcription factor; Transporter