Invertebrate Gustatory Receptors (GRs) are a large and evolutionarily diverse family of sensory receptors known to play important roles in invertebrate taste, smell and thermotransduction. Given the importance of these sensory modalities in host-seeking behavior in important humand disease vectors like mosquitoes, GR family members serve as potentially powerful targets for vector control agents. However, little is known about GR structure and function. We propose a physiological and biochemical analysis of members of two GR subfamilies: Gr43a and Gr28bD. These initial studies will serve as a precursor for a subsequent R01 to carry out structural and functional analyses of these GRs. We propose to achieve these goals in two aims:
Aim #1 : Identify and physiologically characterize multiple orthologs of Gr43a and Gr28bD. Unlike most GRs, Gr43a and Gr28bD orthologs can be functionally characterized in heterologous cells.
In aim 1. a., we will express orthologs of these GRs from additional insect species, including disease vectors and extremophiles, in heterologous cells and characterize their physiological properties. This will enable a comparative analysis of sequence and function among each receptor class.
Aim #2 : Biochemically characterize multiple Gr43a and Gr28bD orthologs. We find Gr43a and Gr28bD orthologs can be partially purified from heterologous cells.
In aim 2, we will expand this approach to incorporate additional orthologs characterized in aim 1 and optimize our purification protocol and explore key properties including oligomeric state and thermal stability in various membrane mimics. This will provide important biochemical information about GR complexes and identify orthologs best suited for subsequent structural analysis. The physiological characterization of multiple Gr43a and Gr28bD orthologs will enable direct examination of evolutionary variation and conservation in GR family function. The expression and purification of multiple family members will provide multiple candidates for biochemistry and structural determination, maximizing the likelihood of success of subsequent GR structural determinations.

Public Health Relevance

The ability of blood-feeding invertebrates like mosquitoes to transmit diseases like malaria, dengue, chikungunya, Zika and West Nile, depends on their ability to detect the sensory cues emitted by their human hosts. Members of the invertebrate Gustatory Receptor (GR) family of sensory cue receptors appear to play critical roles in host-seeking, but little is known about how GRs work at a molecular level, hampering efforts to use them as targets for control agents. We propose to study the functional and biochemical properties of two sub-families of GRs that appear particularly experimentally tractable as a starting point for further analysis of GR structure and function.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21DC018497-02
Application #
10064623
Study Section
Chemosensory Systems Study Section (CSS)
Program Officer
Sullivan, Susan L
Project Start
2020-01-01
Project End
2021-12-31
Budget Start
2021-01-01
Budget End
2021-12-31
Support Year
2
Fiscal Year
2021
Total Cost
Indirect Cost
Name
Brandeis University
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
616845814
City
Waltham
State
MA
Country
United States
Zip Code
02453