Cytosolic Fe-S cluster protein maturation and iron regulation are independent of the mitochondrial Erv1/Mia40 Import System

Hatice K. Ozer, Adrienne C. Dlouhy, Jeremy D. Thornton, Jingjing Hu, Yilin Liu, Joseph J. Barycki, Janneke Balk, Caryn E. Outten

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

The sulfhydryl oxidase Erv1 partners with the oxidoreductase Mia40 to import cysteine-rich proteins in the mitochondrial intermembrane space. In Saccharomyces cerevisiae, Erv1 has also been implicated in cytosolic Fe-S protein maturation and iron regulation. To investigate the connection between Erv1/Mia40-dependent mitochondrial protein import and cytosolic Fe-S cluster assembly, we measured Mia40 oxidation and Fe-S enzyme activities in several erv1 and mia40 mutants. Although all the erv1 and mia40 mutants exhibited defects in Mia40 oxidation, only one erv1 mutant strain (erv1-1) had significantly decreased activities of cytosolic Fe-S enzymes. Further analysis of erv1-1 revealed that it had strongly decreased glutathione (GSH) levels, caused by an additional mutation in the gene encoding the glutathione biosynthesis enzyme glutamate cysteine ligase (GSH1). To address whether Erv1 or Mia40 plays a role in iron regulation, we measured iron-dependent expression of Aft1/2-regulated genes and mitochondrial iron accumulation in erv1 and mia40 strains. The only strain to exhibit iron misregulation is the GSH-deficient erv1-1 strain, which is rescued with addition of GSH. Together, these results confirm that GSH is critical for cytosolic Fe-S protein biogenesis and iron regulation, whereas ruling out significant roles for Erv1 or Mia40 in these pathways.

Original languageEnglish (US)
Pages (from-to)27829-27840
Number of pages12
JournalJournal of Biological Chemistry
Volume290
Issue number46
DOIs
Publication statusPublished - Nov 13 2015

    Fingerprint

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Ozer, H. K., Dlouhy, A. C., Thornton, J. D., Hu, J., Liu, Y., Barycki, J. J., ... Outten, C. E. (2015). Cytosolic Fe-S cluster protein maturation and iron regulation are independent of the mitochondrial Erv1/Mia40 Import System. Journal of Biological Chemistry, 290(46), 27829-27840. https://doi.org/10.1074/jbc.M115.682179