Transfer RNA modification and regulation during blood feeding and vitellogenesis in mosquitoes

Mosquitoes are vectors for numerous human diseases that cause global health concerns. With increasing pesticide resistance and climate change looming, alternative strategies and targets for the population management of mosquitoes are necessary. As key components of protein synthesis, transfer RNAs (tRNA) are likely critical to a multitude of factors for mosquito biology, including blood processing and reproduction. Chemical modifications to tRNA affect the decoding of messenger RNA and subsequently are critical to protein synthesis. Here, we demonstrate that tRNA modifications exhibit sex-associated trends in their abundances as well as types identified in several mosquito species. Anticodon loop modifications were enriched in females which suggests potential roles of modifications in reproduction. To investigate this further, we evaluated tRNA modification abundances post-blood meal consumption and in relation to the production of vitellogenin, the principal yolk protein for mosquitoes. We found modifications to the anticodon to be altered in the hours following a blood meal, specifically later in the digestion cycle when vitellogenin synthesis is at a maximum. Moreover, tRNA modifications correlate with codon usage in vitellogenin, suggesting that specific tRNAs and modifications are likely critical during vitellogenesis. Altogether, these studies indicate that tRNA modifications may be critical to reproduction in mosquitoes and represent an unexplored avenue for population control.