Reliable imaging of ATP in living budding and fission yeast

Abstract

Adenosine triphosphate (ATP) is a major metabolite essential for all living organism. However, our understanding of ATP such as heterogeneity in the cell population or dynamicity in a single living cell are very limited. Here, we optimized an ATP-biosensor QUEEN and monitored the dynamics of ATP with good spatial and temporal resolution in living yeasts. We found stable maintenance of ATP concentration in wild type yeasts regardless of carbon sources or cell cycle stages, suggesting that there exists a mechanism to maintain ATP at a specific concentration. We further found that the ATP concentration is not necessarily an indicator of metabolic activity as there is no clear correlation between ATP level and growth rates. During fission yeast meiosis, we found a reduction in the ATP level suggesting that ATP homeostasis is controlled by differentiation. The use of QUEEN in yeasts offers an easy and reliable assay for ATP dynamicity and will answer various unaddressed questions about eukaryotic cellular metabolism.