Quantitative In Vivo Imaging of ATP Dynamics in Drosophila Using the Ratiometric Biosensor QUEEN

Area of Science:

• Biochemistry
• Cell Biology
• Genetics

Background:

• Genetically encoded ATP biosensors are crucial for monitoring cellular energy status.
• Their application in complex multicellular organisms is limited.
• The QUEEN biosensor, a ratiometric ATP reporter, has shown promise in cell cultures.

Purpose of the Study:

• To generate transgenic Drosophila melanogaster lines expressing the QUEEN-7μ ATP biosensor.
• To validate QUEEN-7μ performance for in vivo ATP level monitoring in fruit flies.
• To establish a system for studying energy metabolism and mitochondrial function in Drosophila.

Main Methods:

• Generation of transgenic Drosophila melanogaster expressing QUEEN-7μ via the GAL4/UAS system.
• Tissue-specific characterization in motor neurons and muscles.
• Validation using pharmacological (mitochanonic acid-5) and genetic (Complex I knockdown, Mitofilin/MIC60 overexpression) perturbations of mitochondrial function.

Main Results:

• QUEEN-7μ successfully enabled tissue-specific ATP monitoring in Drosophila.
• Mitochondrial inhibition decreased the QUEEN-7μ ratio, indicating reduced ATP.
• Treatment with mitochanonic acid-5 and genetic manipulations modulated the QUEEN-7μ ratio consistent with altered ATP synthesis.
• Validated QUEEN-7μ as a reliable ratiometric ATP reporter for quantitative in vivo analysis.

Conclusions:

• QUEEN-7μ is a reliable tool for quantitative in vivo ATP measurement in Drosophila.
• This system offers a versatile platform for investigating energy metabolism and mitochondrial function in a whole organism context.
• Enables future research into cellular energetics and disease models in Drosophila.