Insects and other animals harbor intestinal microbial communities (or ‘gut microbiota’) that play important roles in their biology. However, the processes underlying how these communities assemble in the gut remain largely unexplored. In this collaborative project between researchers at the University of Wisconsin-Madison (US) and the Liverpool School of Tropical Medicine (UK), advanced molecular techniques and experimental approaches will be used to identify the genetic factors contributing to gut microbiota assembly in the mosquito Aedes aegypti, an insect of significant interest because adult females can transmit Zika, dengue, and other arboviruses that cause severe disease in humans. Results from this work will therefore significantly enhance our understanding of mosquito biology with applied relevance to disease transmission in humans and other vertebrates. Results will also expand fundamental knowledge of how animal hosts control gut colonization by bacteria and, conversely, how bacteria adapt to the gut to form stable associations with their animal hosts. Broader impacts of this project to society include the scientific training of postdoctoral researchers and students at the graduate and undergraduate levels to become the next generation of STEM leaders. Educational programming will also be developed for use by the general public and students at the middle, high school, and undergraduate levels. This collaborative US/UK project is supported by the US National Science Foundation and the UK Biotechnology and Biological Sciences Research Council.
This project seeks a mechanistic understanding of host-microbiota interactions during gut microbiome assembly. To date, co-evolution has been investigated largely in bacterial partners of highly stable, long-term associations such as obligate human pathogens. The central hypothesis of this project is that host-microbiota co-adaptation can also occur over repeated interactions spanning very short time scales and is mediated by genetic factors of both hosts and bacteria. Three specific aims will address this hypothesis in the mosquito Aedes aegypti, which harbors simple gut bacterial communities that can be experimentally manipulated. Both A. aegypti and its associated gut bacteria are also genetically tractable. In Aim 1, transcriptome sequencing and functional studies in mosquitoes colonized by defined microbiomes of varying genetic complexity will identify mosquito genes and pathways that control microbiome acquisition and homeostasis. In Aim 2, experimental evolution and transcriptome sequencing of bacteria during gut colonization will identify how bacteria adapt to the mosquito gut environment and establish mixed communities. Finally, studies in Aim 3 will establish whether and to what extent observed host-microbiota interactions are conserved across different host mosquito species. Results will improve understanding of host-microbiota gene interactions during gut colonization and provide valuable long-term genomic and transcriptomic resources to the broader scientific community. This research will also be integrated with education and outreach through the training of postdoctoral and graduate researchers and the development of an undergraduate capstone research project and citizen science toolkit. Results will further be shared through publication in peer-reviewed journals and presentation at scientific meetings.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
