Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2024

Wolbachia elevates host methyltransferase expression and alters the m6A methylation landscape in Aedes aegypti mosquito cells. (104125)

Michael ML Leitner 1 , Valentine VM Murigneux 2 , Kayvan KE Etebari 1 , Sassan SA Asgari 1
  1. School of the Environment, University of Queensland, Brisbane, Queensland, Australia
  2. Bioinformatics, Queensland Cyber Infrastructure Foundation (QCIF), Brisbane, Queensland, Australia

Wolbachia pipientis is an intracellular endosymbiotic bacterium that blocks replication of several arboviruses in transinfected Aedes aegypti mosquitoes. However, the Wolbachia-mediated antiviral mechanism remains largely unknown. We explored the effect of Wolbachia on the expression of the host m6A machinery and if the post-transcriptional modification landscape is altered in the presence of Wolbachia by direct RNA sequencing using the nanopore technology. Mosquito METTL3 and m6A machinery/m6A methyltransferase complex gene expression was elevated in Wolbachia-transinfected cells. Knocking down host m6A-writers, -reader, and -eraser genes using double stranded RNA had no effect on Wolbachia density. Nanopore direct RNA sequencing of wAlbB strain of Wolbachia and Wolbachia-free Aag2 cells showed almost double the number of differentially modified N6-methyladenosine (m6A) sites on mosquito transcripts in Wolbachia colonised cells. m6A in Ae. aegypti were especially enriched within the coding sequence and 3′-untranslated regions. Differential gene expression analysis revealed a critical host factor, transmembrane protein 41B (TMEM41B) required for flavivirus infection upregulated by several fold-change magnitudes. Several classical and non-classical immune-related genes were amongst the downregulated DEG’s. Our findings demonstrate Wolbachia’s ability to alter many intracellular aspects of its host by influencing post-transcriptional m6A modifications and gene expression.