The mitochondrial protein frataxin is essential for biogenesis of catalase in plants

MALIANDI, M.V.; BUSI, M.V.; TUROWSKI, V.R.; LEADEN, L.; ARAYA, A; GOMEZ-CASATI, D.F.

FEBS JOURNAL

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Cambridge; Año: 2011 vol. 278 p. 470 - 481

1742-464X

Frataxin, a conserved mitochondrial protein implicated in cellular ironhomeostasis, has been involved as the iron chaperone that delivers iron forthe Fe–S cluster and heme biosynthesis. However, its role in iron metabolismremains unclear, especially in photosynthetic organisms. In previouswork, we found that frataxin deficiency in Arabidopsis results in decreasedactivity of the mitochondrial Fe–S proteins aconitase and succinate dehydrogenase,despite the increased expression of the respective genes, indicatingan important role for Arabidopsis thaliana frataxin homolog (AtFH).In this work, we explore the hypothesis that AtFH can participate in hemeformation in plants. For this purpose, we used two Arabidopsis lines, atfh-1and as-AtFH, with deficiency in the expression of AtFH. Both lines presentalteration in several transcripts from the heme biosynthetic route with adecrease in total heme content and a deficiency in catalase activity that wasrescued with the addition of exogenous hemin. Our data substantiate thehypothesis that AtFH, apart from its role in protecting bioavailable ironwithin mitochondria and the biogenesis of Fe–S groups, also plays a rolein the biosynthesis of heme groups in plants.