Project description:Ssr4 was experimentally proven to be required for radial growth, aerial conidation, insect infection and virulence-related cellular events in the insect mycopathogen Beauveria bassiana. For in-depth insight into the essential role of Ssr4 in the insect mycopathogen, transcriptomic analysis was carried out via high throughput sequencing (RNA-Seq), resulting in nearly one fourth of the whole genome differentially expressed in the Dssr4 mutant versus wild-type strain.
Project description:Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with poorly understood sublethal effects on insects. Perfluorooctanoic acid (PFOA), one of the most widely distributed legacy PFAS, bioaccumulates globally and is increasingly recognized for altering organismal physiology beyond traditional toxicity endpoints. Here, we use the fruit fly Drosophila melanogaster as a model to examine how PFOA exposure during growth reshapes insect life-history progression and metabolic homeostasis. We show that PFOA exposure induces a tradeoff between developmental rate and physiological robustness, providing a framework for understanding its context-dependent effects on insect fitness. At environmentally relevant concentrations (tens of ppb to low µM), PFOA induces precocious expression of stage-regulated genes and leads to lasting changes in adult metabolic state. At higher concentrations used to probe mechanism, PFOA accelerates larval development, disrupts mitochondrial membrane potential, and increases whole-organism metabolic heat production, indicative of altered mitochondrial energetic efficiency. Consistent with this tradeoff, larvae that develop faster under permissive conditions exhibit heightened sensitivity to environmental stressors, including elevated temperature and reduced food hydration. Together, these findings demonstrate that PFOA disrupts conserved metabolic and developmental processes in a dose- and context-dependent manner, highlighting sublethal effects that may influence insect resilience under environmental stress.
Project description:Mitochondrial metabolic remodeling is a hallmark of the Trypanosoma brucei digenetic life cycle since the insect stage utilizes the cost-effective oxidative phosphorylation to generate ATP, while bloodstream cells switch to less energetically efficient aerobic glycolysis. Due to difficulties in acquiring enough parasites from the tsetse fly vector for biochemical analysis, the dynamics of the parasite´s mitochondrial metabolic rewiring in the vector have remained obscure. Here, we took advantage of in vitro-induced differentiation to follow changes at the RNA levels.