UNDERSTANDING THE GENETIC MECHANISMS OF PHENOTYPIC PLASTICITY IN INSECT MIGRATION
Discovering the genes that drive the long-distance migrations of a major and global insect pest of agriculture.
Tuesday, March 1, 2016 - 10:15
BBSRC Future Leader Fellowship
Each year billions of insects migrate thousands of kilometres in search of food, shelter and places to breed. For many insects, migration is 'switched on' in anticipation of deteriorating habitats, allowing populations to succeed in the face of environmental stress. This ability to respond to environmental cues is highly likely to be due to changes in gene expression (the process of using genetic information to produce functional proteins). This project studies the genetic basis of migration in response to environmental cues using the global insect moth pest, Helicoverpa armigera. By using a computerised tethered flight mill system, it is possible to electronically record the flight behaviour of individual insects as a proxy for migration. The project combines tethered flight behaviour in response to changing environmental cues in the laboratory with molecular tools such as RNA sequencing to determine the genes and biochemical pathways that contribute to migratory flight. The combination of these techniques will contribute greatly to our understanding of the genetic basis of migration in a major insect pest. The results will be applicable to other important migratory moths and will set the benchmark for this area of research for the foreseeable future.
The proposal will combine genomic and post-genomic technologies with cutting edge quantification of flight activity to improve our fundamental understanding of the genetic processes underpinning the plasticity of the migratory response in insect pests. To achieve this goal, the project will be partitioned into three integrated objectives each of which is based on one of three major themes (genotype-environment interactions, gene expression and functional genomics). The proposal builds on preliminary RNA-seq data which demonstrates a clear relationship between the expression of a suite of candidate genes and flight activity in the migratory moth pest, Helicoverpa armigera (Jones et al. 2015, Molecular Ecology).
The three objectives of the project are:
Investigating the phenotypic plasticity of the migratory response in H. armigera
This objective will use the tethered flight mill system to quantify flight propensity in adult H. armigera exposed during the larval stage to three environmental cues that can result in differential migratory responses; density, photoperiod and nutrition.
Deciphering the relative contribution of a candidate gene set on the plasticity of the migratory response.
This objective will quantify the expression of candidate genes in H. armigera exposed to the three environmental variables in the objective.
Functional validation of migratory candidate genes.
Candidate genes identified in the second objective will be functionally explored using CRISPR-Cas9 and over-expressed in transgenic Drosophila to determine their relative role in flight performance.
Nanjing Agricultural University