Research Project
Grant-in-Aid for Scientific Research (B)
Mitochondria have been shown to be the organelle to play a central role in iron metabolism by generating prosthetic groups of iron such as heme or iron-sulfur (Fe-S) cluster. However, transport of iron into mitochondria or export of iron prosthetic groups from the organelle as well as the roles of mitochondria play in the control of cellular iron metabolism have not been clarified yet. Here we analyzed roles of mitochondria play in iron metabolism.Aftlp is an iron-responsive transcriptional activator that plays a central role in maintaining iron homeostasis in Saccharomyces cerevisiae and its activity is regulated primarily by iron-induced nuclear export of the protein. We have shown that Msn5p is the nuclear export receptor (exportin) for Aftlp. Msn5p recognizes Aftlp in the iron-replete condition and the iron-induced intermolecular interaction of Aftlp are essential for its recognition by Msn5p. Mutation of Cys291 of Aftlp to Phe, which causes Aftlp to be retained in the nucleus and results in constitutive activation of Aftl-target genes, disrupts the intermolecular interaction of Aftlp.We also analyzed the roles of the molecules involved in Fe-S cluster biogenesis and transport using chicken DT40 B cells. Disruption of the molecules involved in Fe-S biogenesis in mitochondria abolishes Fe-S loading to IRP1 and renders the protein to the IRE binding form. However, disruption of the molecules involved in cytoplasmic Fe-S assembly leads IRP1 to degradation by the proteasome in condition of iron-replete although Fe-S cluster cannot bind to the protein in those cells. These results suggest that the IRE-binidng activity of IRP1 is regulated via Fe-S dependent and independent pathways.
All 2007 2006 2005 2004 Other
All Journal Article (35 results)
Molecular Biology of the Cell (In revision)
J. Biol. Chem. 281
Pages: 7384-7391
J. Biol. Chem 281
Pages: 17743-17750
Genomics Proteomics Bioinformatics. 4
Pages: 1-9
J.Biol.Chem. 281
The Journal of Biological Chemistry 281
Genomics, Proteomics & Bioinformatics 4
J.Biol.Chem. 281(in press)
Proc. Natl. Acad. Sci. USA 102
Pages: 13956-13961
J Biol Chem 280
Pages: 637-643
J. Biol. Chem. 280
Pages: 30956-30962
Mol Cell 19
Pages: 171-181
Methods Enzymol 398
Pages: 256-271
Proc.Natl.Acad.Sci. USA 102
J.Biol.Chem. 280
Mol.Cell. 19
Methods Enzymol. 398
Proc.Natl.Acad.Sci. 102
Molecular Cell 19
J.Biol.Chem 280
Cell. Mol. Life Sci. 61
Pages: 49-68
Cell.Mol.Life Sci. 61
生化学 76
Pages: 441-444
10013052821
Nat.Struct.Mol.Biol. 11
Pages: 365-370
IUBMB Life 56
Pages: 193-201
Genes Cells. 9
Pages: 865-875
Molecular Biology of the Cell (In press)
Genomics Proteomics and Bioinformatics (in press)