PubMed Health⌕ Search

Biomedical subjects

Sylviane Dewaele

Publications and source records attributed to Sylviane Dewaele.

2 recordsLinked to original sources

Expression of the human ferritin light chain in a frataxin mutant yeast affects ageing and cell death.

Ferritin is one of the major eukaryotic proteins involved in regulating iron metabolism and maintaining iron homeostasis. However, Saccaromyces cerevisiae is an exception, possessing no ferritin and using other means to store excess iron. The only potential iron storage protein identified in yeast so far is the homologue of human frataxin (YFH1p). In this study, we found that dysfunction of yeast frataxin shortens mean lifespan by 49% compared to the WT control. Interestingly, the human ferritin L gene can, at least partially, complement the function of yeast frataxin, extending lifespan and protecting cells from death induced by oxidative stress or excess iron. Our findings indicate that ferritin L can perform functions in yeast that are similar to its functions in mammals, and suggest that common mechanisms may exist for preventing iron and oxidative damage in single- and multi-cellular eukaryotic organisms. Clearly, elucidation of the function of human ferritin in yeast would help in gaining a better understanding the molecular basis of iron storage diseases.

Aging↗

A high-throughput screening system for genes extending life-span.

We developed a high-throughput functional genomic screening system that allows identification of genes prolonging life-span in the baker's yeast Saccharomyces cerevisiae. The method is based on isolating yeast mother cells with extended number of cell divisions as indicated by the increased number of bud scars on their surface. Fluorescently labelled Wheat Germ Agglutinin was used for specific staining of chitin, a major component of bud scars. Screening of a human HepG2 cDNA expression library in yeast resulted in the isolation of 12 yeast transformants with a potentially prolonged life-span. The transgene in one of the lines was identified as ferritin light chain (FTL) and studied in more detail. Yeast cells containing FTL showed an enhanced iron and H(2)O(2) resistance, a reduced cell death rate and an increased number of cell divisions. Overexpression of FTL in the nematode Caenorhabditis elegans resulted in a life-span increase of 8% confirming our yeast observations in a multicellular organism. Our data demonstrate that this method permits a fast screening of libraries for hunting genes involved in ageing processes.

Ferritins↗