Abstract
Some mRNA encoding proteins related to iron metabolism contain a specific stem-loop structure--iron responsive element (IRE)-in the 5' UTR. Binding of the iron regulatory protein (IRP) to the IRE, in response to decreases in cellular iron levels, leads to a block in translation of these mRNAs. We here describe the drosophila melanogaster succinate dehydrogenase iron protein (SDH-IP) as a fourth example of an mRNA species being translationally regulated by an IRE, based on iron dependent regulation of SDH-IP translation in vivo by immunoprecipitations and northern blotting in drosophila cell lines. Addition of hemin to the drosophila cells lead to fragmentation of the SDH-IP, which might suggest additional mode to specifically down-regulate the expression of this protein and Krebs cycle function.
