Genome plasticity in tiger mosquitoes: biological significance and relevance for pest management

Project in brief

Mutations are the key substrate of evolution and adaptation. Beside single nucleotide mutations, transposable elements (TEs) have been shown to be a major source of both genetic and phenotypic variation in the model organism Drosophila. TEs can be major players of genome plasticity, and their replication and movement can introduce genetic variability that facilitates local adaptation. This is particularly relevant for the tiger mosquito Aedes albopictus (Aalb), an invasive species whose genome is extremely rich in TEs and which quickly spread under novel environmental conditions in the invaded regions.

In this project we intend to fill a major knowledge gap: clarify the relationship between thermal stress and TEs mobility and determine if temperature is a possible effector of genome plasticity and adaptation in Aalb. We will provide better understanding on whether TEs can play a role in fast local adaptation, and therefore in the invasiveness, of these mosquitoes in Italy. This will ultimately allow us to provide a forecast for the long term evolution of Ae. albopictus in Italy.

Project objectives

By means of genome sequencing and TEs content characterization we will:

  1. experimentally test the effects of thermals stress on TEs activity in a Aalb lab-reared population; 
  2. verify whether Aalb wild populations sampled along a thermal gradient in Italy show a TEs landscape compatible with the mobilisation pattern observed in the lab experiments; 
  3. compare the TEs content of Aalb genome with that of closely related Aedes flavopictus and of emerging invasive species Aedes japonicus and Aedes koreicus to understand if TEs can be associated with invasive success. 

During the sampling stage, we also plan to engage local schools, involving students in the sampling process and organising dedicated lectures and activities to explain the role of genomics studies in providing better understanding of these invasive pests.

Impact

This work will have a significant scientific impact in evolutionary biology, because we will provide a better understanding of the adaptive role of genomic plasticity induced by TEs. This project will also have social and public health impacts, because our results will help the development of predictive tools on the adaptive potential of invasive species, including when experiencing climate change-induced stress.

Funding

Funded by the European Union under NextGenerationEU. PRIN 2022 Prot. n. 2022YNL8ZH

Team

 

photo: Zadra et al.Insects 2023, 14, 904. https://doi.org/10.3390/insects14120904