title: The hierarchy of transition metal homeostasis: iron controls manganese accumulation in a unicellular cyanobacterium.
abstract: Iron and manganese are part of a small group of transition metals required for photosynthetic electron transport. Here, we present evidence for a functional link between iron and manganese homeostasis. In the unicellular cyanobacterium, Synechocystis sp. PCC 6803, Fe and Mn deprivation resulted in distinct modifications of the physiological status. The effect on growth and photosynthetic activity under Fe limitation were more severe than those observed under Mn limitation. Moreover, the intracellular elemental quotas of Fe and Mn were found to be linked. Fe limitation reduced the intracellular Mn quota. Mn limitation did not exert a reciprocal effect on Fe quotas. Microarray analysis comparing Mn and Fe limitation revealed a stark difference in the extent of the transcriptional response to the two limiting conditions, reflective of the physiological responses. The effects of Fe limitation on the transcriptional network are widespread while the effects on Mn limitation are highly specific. Our analysis also revealed an overlap in the transcriptional response of specific Fe and Mn transporters. This overlap provides a framework for explaining Fe limitation induced changes in Mn quotas.
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Shir
authors.initials: S
authors.lastname: Sharon
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Eitan
authors.initials: E
authors.lastname: Salomon
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Chana
authors.initials: C
authors.lastname: Kranzler
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Hagar
authors.initials: H
authors.lastname: Lis
authors.affiliation: Institute for Theoretical Biology, Humboldt University Berlin, Invalidenstraße 43, D-10115 Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Lehmann
authors.affiliation: Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Georg
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Hagit
authors.initials: H
authors.lastname: Zer
authors.affiliation: Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany.
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Hess
authors.affiliation: Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem, Israel. Electronic address: nir.ke@mail.huji.ac.il.
authors.forename: Nir
authors.initials: N
authors.lastname: Keren
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018533:Biomass; D027682:Cation Transport Proteins / Q000235:genetics; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006706:Homeostasis / Q000235:genetics*; D015151:Immunoblotting; D007501:Iron / Q000378:metabolism*; D008345:Manganese / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010100:Oxygen / Q000378:metabolism; D010788:Photosynthesis; D045331:Photosystem I Protein Complex / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D046939:Synechocystis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D027682:Cation Transport Proteins; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D022661:RNA, Untranslated; D008345:Manganese; D007501:Iron; D010100:Oxygen