Dual-color system for simultaneously monitoring intracellular Ca2+ and ATP dynamics

Although Ca2+ regulates energy metabolism through diverse pathways, there have been no methods to monitor both Ca2+ dynamics and metabolic activity simultaneously. Here we report a novel system for simultaneously monitoring intracellular Ca2+ and ATP levels using a blue-emitting photoprotein and a red-emitting beetle luciferase. Using this system, we monitored the dynamic changes simultaneously in both intracellular Ca2+ and ATP levels during chondrogenesis. We have found that both intracellular Ca2+ and ATP levels oscillated and their oscillations have a nearly antiphase relationship with each other. The dual-color monitoring system is useful for studying the relationship between Ca2+ dynamics and energy metabolic pathways. (c) 2012 Elsevier Inc. All rights reserved.