Characterisation of some iron proteins in Drosophilia melanogaster and Pacifastacus leniusculus
2000 (English)Doctoral thesis, comprehensive summary (Other academic)
The cDNA cloning of the 76-kDa protein, an immune protein from crayfishhaemocytes, shows that it is similar to a family of haem-containing peroxidases.In addition to its cell adhesion activity it has also peroxidase activity, and theprotein was named peroxinectin. The cell adhesion is probably mediated by aKGD-motif present in peroxinectin.
In mammals, the iron-regulatory proteins (IRP) can bind the iron-responsive element (IRE), present in the mRNAs of some iron proteins andthereby regulate their expression. IRPs are also present in the invertebrates,Drosophila melanogaster, and Pacifastacus leniusculus. Two DrosophilaIRP1s, IRP1A and IRP1B, were cloned. Recombinant IRP1A binds specifically toIREs and both IRP1A and IRP1B have aconitase activity. The Drosophilamitochondrial aconitase (mAc) was cloned and shows similarity to the IRPs.Interestingly, the Drosophila mAc mRNA lacks the IRE, in contrast tomammalian mAc transcripts, which have IREs. This supports the idea thatDrosophila has another IRP regulated step in the citric acid cycle.
Several transcripts encoding the same ferritin subunit in D.melanogaster were isolated. These transcripts are generated by alternativesplicing and differential poly-adenylation. The expressions of these aredevelopmentally regulated, and are modulated in response to the iron level. AnIRE is present within the alternatively spliced intron. Furthermore, the transcriptencoding crayfish ferritin has an atypical IRE. Both the Drosophila and crayfish ferritin IREs bind specifically to IRPs.
Translocation of iron and other metal-ions through the bilipidmembrane is depending on transport systems, and in Drosophila three members of the ZIP family of metal-ion transporters were identified and their expression was studied.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis , 2000. , 45 p.
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-232X ; 536
Research subject Physiological Mycology
IdentifiersURN: urn:nbn:se:uu:diva-247ISBN: 91-554-4715-5OAI: oai:DiVA.org:uu-247DiVA: diva2:161858
2000-05-12, Lecture hall 05.01058, Evolutionary Biology Centre (EBC), Uppsala, Uppsala, 10:00