title: Comparative genomics allows the discovery of cis-regulatory elements in mosquitoes.
abstract: The discovery and mapping of cis-regulatory elements is important for understanding regulation of gene transcription in mosquito vectors of human diseases. Genome sequence data are available for 3 species, Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus (Diptera: Culicidae), representing 2 subfamilies (Culicinae and Anophelinae) that are estimated to have diverged 145 to 200 million years ago. Comparative genomics tools were used to screen genomic DNA fragments located in the 5'-end flanking regions of orthologous genes. These analyses resulted in the identification of 137 sequences, designated "mosquito motifs," 7 to 9 nucleotides in length, representing 18 families of putative cis-regulatory elements conserved significantly among the 3 species when compared to the fruit fly, Drosophila melanogaster. Forty-one of the motifs were implicated previously in experiments as sites for binding transcription factors or functioning in the regulation of mosquito gene expression. Further analyses revealed associations between specific motifs and expression profiles, particularly in those genes that show increased or decreased mRNA abundance in females following a blood meal, and those accumulating transcription products exclusively or preferentially in the midgut, fat bodies, or ovaries. These results validate the methodology and support a relationship between the discovered motifs and the conservation of hematophagy in mosquitoes.
authors.affiliation: Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA.
authors.forename: Douglas H
authors.initials: DH
authors.lastname: Sieglaff
authors.forename: W Augustine
authors.initials: WA
authors.lastname: Dunn
authors.forename: Xiaohui S
authors.initials: XS
authors.lastname: Xie
authors.forename: Karyn
authors.initials: K
authors.lastname: Megy
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Marinotti
authors.forename: Anthony A
authors.initials: AA
authors.lastname: James
mesh_terms: D000818:Animals; D009033:Culicidae / Q000235:genetics*; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D023281:Genomics; D005810:Multigene Family / Q000235:genetics; D010802:Phylogeny; D012045:Regulatory Sequences, Nucleic Acid