Structure and location of a ferritin gene of the yellow fever mosquito Aedes aegypti

We have isolated and sequenced a genomic clone encoding the 24- and 26-kDa ferritin subunits in the mosquito Aedes aegypti (Rockefeller strain). The A . aegypti gene differs from other known ferritin genes in that it possesses an additional intron and an unusually large second intron. The additional intron is located within the 5' untranslated region, between the CAP site a nd the start codon. The second intron contains numerous putative transposab le elements. In addition, unlike the human and rat ferritin genes, the A. a egypti ferritin gene is a single copy gene, located at 88.3% FLpter on the q-arm of chromosome 1. Primer extension analysis indicates that the A. aegy pti ferritin gene has multiple transcriptional start sites. A differential usage of these sites is observed with varied cellular iron concentrations.