bioRxiv Science⌕ Search

Biology subjects

Uhran, M.

Publications and source records attributed to Uhran, M..

2 recordsLinked to original sources

Drought tolerance of Aedes aegypti mosquito eggs is influenced by adaptation to local climate conditions and associations with humans

Urbanization is intensifying human interactions with mosquitoes, exacerbating public health challenges. Densely populated areas provide ideal conditions for container-dwelling mosquitoes, with increased host availability and the presence of artificial breeding sites. These anthropophilic mosquitoes often exhibit distinct ecological adaptations compared to their rural counterparts. Since mosquito eggs are immobile and remain at the site of oviposition, they provide a valuable lens for assessing how urbanization, climate-driven shifts in temperature, and drought affect mosquito reproductive success. This study examined Ae. aegypti egg viability under varying temperature and dry conditions over five months, focusing on lineages with distinct ancestries from West African populations. Mosquitoes collected from urban habitats with a high human preference demonstrated higher egg survival under prolonged arid conditions. Analysis of climatic factors revealed that dry season temperature and precipitation during wet periods are significant predictors of egg drought tolerance. Modeling future climate scenarios based on input from our egg viability results suggests a projected shift and expansion in the seasonal survival window for Ae. aegypti by the end of the century. This study highlights the importance of understanding environmental constraints on the drought tolerance of mosquito eggs to predict and mitigate future mosquito outbreaks.

physiology↗

A microbiome-derived transfer RNA modification underlies behavioral optimums and predator avoidance in mosquito larvae

The gut microbiome is a rich source of nutrients that are critical to the development and biology of eukaryotes. Transfer RNAs (tRNAs) are essential components of protein synthesis, and some chemical modifications to tRNA rely on the availability of microbiome-derived nutrients. In eukaryotes, the micronutrient queuosine (Q) is salvaged from the microbiome or diet and then incorporated into eukaryotic tRNA to influence the speed and efficiency of protein synthesis. Here, we examine the role of microbiome-derived Q in mosquito larval development and behavior. When mosquito larvae are grown with a microbiome incapable of synthesizing Q, there is a significant impact on tyrosine levels and processes, which correlate with defects in behavior and cuticle formation. Due to defects in movement and behavioral responses, Q-deficient larvae demonstrate impaired predator evasion, leading to higher instances of capture by predaceous beetle larvae. The broad effects of Q-deficiency in mosquito larvae highlight the importance of microbiome-derived nutrients for eukaryotic physiology and behavior.

physiology↗