The arabidopsis atfh frataxin : genetic approach with inducible rnai to investigate its role in the iron trafficking in mitochondria

Frataxin is present in mitochondria of all eukaryotes as well as in the cytoplasm of bacteria. Experimental evidence suggests that frataxin acts as an iron-chaperone protein, donating iron to the proteins involved in [Fe-S] cluster assembly and heme synthesis. It also possibly contributes to the process of iron detoxification and storage. The frataxin homolog from Arabidopsis thaliana (AtFH) is a single nuclear-encoded gene targeted to mitochondria. We have previously shown that [1] the knocking out of AtFH gene causes arrest of Arabidopsis embryo development at the globular stage. Consistently with that, we have also shown by in situ hybridisation that AtFH is expressed, in wt Arabidopsis plants, in ovule primordia as well as in embryos at various stages of development. We are currently producing Arabidopsis transgenic lines, by inducible RNAinterference, in which microRNA can switch off AtFH frataxin transcript accumulation upon plant treatment with either ethanol or dexametasone. Such approach will allow to overcome experimental constraints due to embryo lethality of AtFH KO. [1] Vazzola et al. (2007) FEBS Letters 581:667-672. EXPRESSION