Subach’s group from Russia developed FGCaMP7, a novel calcium indicator that contains a subunit from fungi which prevents its interaction with intracellular calmodulin. This ratiometric sensor can detect active and silent neurons in vivo. Our colleagues developed the sensor and tested it in neuronal cultures, mouse visual cortex, and hippocampus in vivo. In our lab, we helped them to characterize its properties in zebrafish. The paper that describes our results has been recently published in the International Journal of Molecular Sciences.