Genome sequence of Aedes aegypti, a major arbovirus vector

Abstract

We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species.

Figure 1

Relative genomic content of annotated TEs and other sequences in Aedes aegypti. TEs have been deposited in TEfam, a relational database for submission, retrieval, and analysis of TEs (http://tefam.biochem.vt.edu).

Figure 2

Transcriptome analyses of Aedes aegypti. A. Functional class distributions of genes that are enriched in pre-adult stages (DEV) and the adult female stage (ADULT) (Table S9). B. Proportions of functional gene classes expressed as the percentage of the total umber of genes that are enriched in pre-adult stages (DEV), adult female stage (ADULT) and constitutively expressed genes (CONST.). C and D. same as A and B for genes enriched in the male, female and genes common (CONST.) for both sexes (Table S17). Functional classes are: Immunity (IMM), redox, oxidoreductive stress (RED/STE), chemosensory reception (CSR), blood and sugar food digestive (DIG), proteolysis (PROT), cytoskeletal and structural (CYTISTR), transport (TRP), replication, transcription and translation (R/T/T), metabolism (MET), diverse functions (DIV), unknown functions (UNK). The total number of genes in each category is indicated in parenthesis.

Figure 3

Orthology and chromosomal synteny between Ae. aegypti, An. gambiae and D. melanogaster. A. Each circle represents a gene set for Ae. aegypti (Ae), An .gambiae (An) and D. melanogaster (Dm). Because a gene can be involved in several homologies, gene sets do not always have the same number of genes within intersections; e.g.: in the Ae/Dm comparison, 943 Ae genes are similar to Dm while 925 Dm genes are similar to Ae. B. Aedes aegypti chromosomes are represented in grey (not to scale). Chromosome arms are designated as ‘p’ and ‘q’ - with no arm distinctions for chromosome 1. Colored chromosomes represent the syntenic chromosome from An. gambiae (An) or D. melanogaster (Dm) (not to scale). Solid lines link the Ae. aegypti chromosome to their primary syntenic chromosome and dashed lines to their secondary syntenic chromosome. The number of Ae orthologs to An and Dm chromosome arms is indicated and the total number of orthologs on the Ae chromosome arm to Ae or Dm is shown in italic in parenthesis.