Open AccessDrosophila melanogaster transferrin
Author(s) -
Yoshiga Toyoshi,
Georgieva Teodora,
Dunkov Boris C.,
Harizanova Nedjalka,
Ralchev Kiril,
Law John H.
Publication year - 1999
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.1999.00173.x
Subject(s) - transferrin , biology , complementary dna , microbiology and biotechnology , cdna library , drosophila melanogaster , northern blot , gene , biochemistry
Drosophila melanogaster transferrin cDNA was cloned from an ovarian cDNA library by using a PCR fragment amplified by two primers designed from other dipteran transferrin sequences. The clone (2035 bp) encodes a protein of 641 amino acids containing a signal peptide of 29 amino acids. Like other insect transferrins, Drosophila transferrin appears to have a functional iron‐binding site only in the N‐terminal lobe. The C‐terminal lobe lacks iron‐binding residues found in other transferrins, and has large deletions which make it much smaller than functional C‐terminal lobes in other transferrins. In‐situ hybridization using a digoxigenin labeled transferrin cDNA probe revealed that the gene is located at position 17B1‐2 on the X chromosome. Northern blot analysis showed that transferrin mRNA was present in the larval, pupal and adult stages, but was not detectable in the embryo. Iron supplementation of the diet resulted in lower levels of transferrin mRNA. When adult flies were inoculated with bacteria ( Escherichia coli ), transferrin mRNA synthesis was markedly increased relative to controls.