Vitelline membrane genes in the yellow fever mosquito, Aedes aegypti
AuthorEdwards, Marten John, 1965-
AdvisorHagedorn, Henry H.
MetadataShow full item record
PublisherThe University of Arizona.
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
AbstractThree vitelline membrane (envelope) genes in Aedes aegypti mosquitoes were studied. A genomic clone corresponding to a novel vitelline membrane gene (15a-3) was isolated. The predicted peptide sequence of 15a-3 is similar to those of the A. aegypti vitelline membrane genes 15a-1 and 15a-2. The deduced amino acid sequences of 15a-1, 15a-2 and 15a-3 contain a conserved region of 45 residues. This region overlaps with a conserved region in four Drosophila melanogaster vitelline membrane genes. Genomic clones corresponding to 15a-1, 15a-2 and 15a-3 coding regions. A 360 bp region 5' of the 15a-2 coding region was identified with 72% identity to a region upstream of the A. aegypti VgA1 vitellogenin gene Sequences with similarity to a 20-hydroxyecdysone response element consensus sequence were found upstream of the three coding regions. The transcriptional regulation of three A. aegypt vitelline membrane genes was examined. The sites and timing of expression of the three transcripts were determined by Northern blot analysis and whole-mount in situ hybridization using mutually exclusive probes. The temporal pattern of 15a-1, 15a-2 and 15a-3 expression was similar. The spatial pattern of expression differed between the three genes. Only 15a-2 was expressed at the anterior region in addition to the remainder of the follicle. 15a-1 and 15a-3 wee only expressed in the mid and posterior regions of the follicle. Expression of 15a-1 was higher in ovaries that were dissected at intervals of 0, 2, 10 and 24 h after a blood meal and were cultured in medium containing 20-hydroxyecdysone, as compared to control incubations. In ovaries that were dissected at 36 h after a blood meal, incubation in 20-hydroxyecdysone had no effect on 15a-1 expression, as compared to control incubations.
Degree ProgramGraduate College