Ionized calcium (Ca2+) and reactive oxygen species (ROS) are two essential second messengers that cross influence each-other. Intracellular, local Ca2+ and ROS levels are tightly controlled by a number of molecular sources and sinks. Using novel genetically encoded detectors and generators of Ca2+ and ROS and theoretical models and predictions, we aim to 1) Trigger and measure subcellular ROS production and determine their influence on redox regulation of SOCE, cellular transcription and programming. 2) Investigate the functional consequences of the localized SOCE and/or redox regulation in healthy neurons and melanoma cancer cells.