Linked Life Data

19460301

Source:http://linkedlifedata.com/resource/pubmed/id/19460301

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-5-25
pubmed:abstractText
Friedreich's ataxia is generally associated with defects in [Fe-S] cluster assembly/stability and heme synthesis and strong susceptibility to oxidative stress. We used the yeast (Saccharomyces cerevisiae) model of Friedreich's ataxia to study the physiological consequences of modulating the expression of the frataxin gene (YFH1). We show that the number of frataxin molecules per wild-type cell varies from less than 200 to 1500 according to the iron concentration in the medium. Cells overexpressing YFH1 on a plasmid (2muYFH1; about 3500 molecules Yfh1/cell) took up more iron than wild-type cells and displayed defective [Fe-S] cluster assembly/stability in vivo. By contrast, endogenous mitochondrial iron was more available to ferrochelatase in 2muYFH1 cells than in wild-type cells, resulting in higher levels of heme synthesis in vitro. Frataxin overproduction resulted in a shift from frataxin trimers to frataxin oligomers of higher molecular mass in the mitochondrial matrix. Much fewer carbonylated proteins were present in 2muYFH1 cells, and these cells were more resistant to oxidizing agents than wild-type cells, which probably resulted from the lower production of hydrogen peroxide by the mitochondria of 2muYFH1 cells compared to wild-type cells. To our knowledge, this work is the first description where major frataxin-related phenotypes ([Fe-S] cluster assembly and heme synthesis) can be split in vivo, suggesting that frataxin has independent roles in both processes, and that the optimal conditions for these independent roles are different.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1872-8278
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
130-8
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Overexpression of the yeast frataxin homolog (Yfh1): contrasting effects on iron-sulfur cluster assembly, heme synthesis and resistance to oxidative stress.
pubmed:affiliation
Laboratoire d'Ingéniérie des Protéines et Contrôle Métabolique, Département de Biologie des Génomes, Institut Jacques Monod, UMR7592 CNRS, Université Paris Diderot and UPMC, Tour 43, 2 Place Jussieu, F-75251 Paris cedex 05, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't