Aedes aegypti transmits a number of arboviral diseases including dengue fever, which threatens virtually one half of the human population. Recent physical and genetic mapping efforts assigned 71% of the original draft genome assembly to the mosquito chromosomes. However, the Ae. aegypti genome assembly still remains highly fragmented. Moreover, both mapping approaches determined high rates of misassembly in the existing genomic supercontigs. The lack of a high-quality genome assembly has hindered population and evolutionary genomics studies. Two subspecies, Ae. aegypti aegypti and Ae. aegypti formosus, have been described based on body coloration. These subspecies remarkably differ from each other in their worldwide distribution, association with humans, and ability to transmit pathogens. Based on our preliminary data, we hypothesize that chromosomal inversions contribute to the establishment and maintenance of genomic and phenotypic divergence in aedini mosquitoes. Polymorphic inversions are often responsible for epidemiologically important phenotypes in Anopheles populations but they have never been directly observed in Aedes. Our long-term goal is to understand the underlying genomic determinants of epidemiologically important phenotypic and behavioral differences of the Ae. aegypti subspecies. Toward this end, we propose three specific aims for this project: 1) improve the genome assembly and gene annotation of Ae. aegypti based on Pacific Biosciences RS sequencing data; 2) develop a high- resolution physical map for the Ae. aegypti genome; 3) use the new genome assembly as a reference to detect inversions in 2 subspecies of Ae. aegypti and in a sister taxon, Ae. mascarensis. The innovative strategy of integrating a powerful 3rd generation sequencing technology with physical chromosome mapping will create an improved high-quality genome assembly that will make possible the discovery of chromosomal inversions in Ae. aegypti and will stimulate future genetic studies aimed at preventing mosquito- borne disease transmission.

Public Health Relevance

The mosquito Aedes aegypti is the major vector of dengue fever that threatens nearly one half of the world's human population. To facilitate the development of new technologies for control of vector-borne infectious diseases, this project will improve the existing genome assembly for Aedes aegypti using Pacific Biosciences RS sequencing and physical mapping. The improved genome assembly will serve as a reference for the screening of chromosomal inversions in 3 aedini strains.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI121853-02
Application #
9198480
Study Section
Vector Biology Study Section (VB)
Program Officer
Costero-Saint Denis, Adriana
Project Start
2016-01-01
Project End
2018-12-31
Budget Start
2017-01-01
Budget End
2018-12-31
Support Year
2
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Virginia Polytechnic Institute and State University
Department
Zoology
Type
Earth Sciences/Resources
DUNS #
003137015
City
Blacksburg
State
VA
Country
United States
Zip Code
24061
Dickson, Laura B; Sharakhova, Maria V; Timoshevskiy, Vladimir A et al. (2016) Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements. PLoS Negl Trop Dis 10:e0004626