title: Chaperonin 20 might be an iron chaperone for superoxide dismutase in activating iron superoxide dismutase (FeSOD).
abstract: Activation of Cu/Zn superoxide dismutases (CuZnSODs) is aided by Cu incorporation and disulfide isomerization by Cu chaperone of SOD (CCS). As well, an Fe-S cluster scaffold protein, ISU, might alter the incorporation of Fe or Mn into yeast MnSOD (ySOD2), thus leading to active or inactive ySOD2. However, metallochaperones involved in the activation of FeSODs are unknown. Recently, we found that a chloroplastic chaperonin cofactor, CPN20, could mediate FeSOD activity. To investigate whether Fe incorporation in FeSOD is affected by CPN20, we used inductively coupled plasma mass spectrometry to analyze the ability of CPN20 to bind Fe. CPN20 could bind Fe, and the Fe binding to FeSOD was increased with CPN20 incubation. Thus, CPN20 might be an Fe chaperone for FeSOD activation, a role independent of its well-known co-chaperonin activity.
authors.affiliation: Institute of Plant Biology and Department of Life Science; National Taiwan University; Taipei, Taiwan.
authors.forename: Wen-Yu
authors.initials: WY
authors.lastname: Kuo
authors.affiliation: Institute of Plant Biology and Department of Life Science; National Taiwan University; Taipei, Taiwan.
authors.forename: Chien-Hsun
authors.initials: CH
authors.lastname: Huang
authors.affiliation: Institute of Plant Biology and Department of Life Science; National Taiwan University; Taipei, Taiwan.
authors.forename: Tsung-Luo
authors.initials: TL
authors.lastname: Jinn
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D056384:Group I Chaperonins / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C478767:Cpn20 protein, Arabidopsis; D007501:Iron; D013482:Superoxide Dismutase; D056384:Group I Chaperonins
keywords: Arabidopsis; FeSOD; SOD activation; chaperonin 20; iron chaperone; iron homeostasis