Disease relevance of SdhB

• The deduced amino-acid (aa) sequence shows strong similarities with Ip peptides from Escherichia coli, yeasts, plants and mammals, with 100% aa identity around the three Cys clusters which form the non-heme iron-sulfur centers [1].

High impact information on SdhB

• Furthermore, Drosophila SDHb represents the second example, after porcine mitochondrial aconitase, of an enzyme of the citric acid cycle whose mRNA possesses all necessary features for translational regulation by cellular iron levels [2].
• In situ hybridization on polytene chromosomes maps SdhB to band 42D 1-5 on the right arm of the second chromosome next to the centromere [1].
• A 2.7-kb fragment containing SdhB has been sequenced and shown to comprise the entire transcribed region and more than 900 bp of promoter region [1].
• We have cloned the Drosophila melanogaster Ip-encoding gene (SdhB) by genomic library screening using the human Ip-encoding cDNA as a probe at low stringency [1].
• 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 [3].

Anatomical context of SdhB

• 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 [3].

References