Frataxin Is Localized to Both the Chloroplast and Mitochondrion and Is Involved in Chloroplast Fe-S Protein Function in Arabidopsis

VALERIA R. TUROWSKI; CINDY AKNIN; MARIA V. MALIANDI; CELESTE BUCHENSKY; LAURA LEADEN; DIEGO A. PERALTA; MARIA V. BUSI; ALEJANDRO ARAYA; DIEGO F. GOMEZ CASATI

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2015

1932-6203

Frataxin plays a key role in eukaryotic cellular iron metabolism, particularly in mitochondrialheme and iron-sulfur (Fe-S) cluster biosynthesis. However, its precise role has yet to be elucidated. In this work, we studied the subcellular localization of Arabidopsis frataxin, AtFH, using confocal microscopy, and found a novel dual localization for this protein. We demonstrate that plant frataxin is targeted to both the mitochondria and the chloroplast, where it may play a role in Fe-S cluster metabolism as suggested by functional studies on nitritereductase (NIR) and ferredoxin (Fd), two Fe-S containing chloroplast proteins, in AtFH deficient plants. Our results indicate that frataxin deficiency alters the normal functioning ofchloroplasts by affecting the levels of Fe, chlorophyll, and the photosynthetic electron transport chain in this organelle.