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

We have isolated and sequenced a genomic clone encodihg the 24- and 26- kDa ferritin subunits in the mosquito Aedes aegypti (Rockefeller strain). The A. aegypti gene differs from other known ferrtin 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 and the start codon. The second intron contains numerous putative transposable elements. In addition, unlike the human and rat ferritin genes, the A. aegypti 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. aegypti ferritin gene has multiple transcriptional start sites. A differential usage of those sites is observed with varied cellular iron- concentrations.