Cellular homeostasis is driven by reduction-oxidation (redox) systems. A fine-tuned interaction between reactive oxygen species (ROS) production and a diversified antioxidant system shapes the redox state of cells, which is highly responsive to environmental perturbations in plants. Hydrogen peroxide (H2O2) is the most efficient signalling ROS molecule due to its relative stability and ability to migrate within and between cells. H2O2-signalling is a pivotal feature during environmental stress conditions such as pathogen infections, pollution, temperature and water stresses. Although the basic understandings of redox-based perturbation and signalling within various organelles is present, profound knowledge on the regulatory mechanisms that drive redox-dependent gene expression is lacking. We hypothesise that oxidative posttranslational modifications initiated by H2O2 are crucial mediators of nuclear activities. In order to spy on the operations of redox systems within the command centre of the cell, we will innovate ground breaking molecular tools to penetrate unexplored niches of the nucleus in a highly specific manner. With a recently developed technology (oxiTRAP), we are now able to generate an unprecedented spatial resolution of redox-sensitive targets at nuclear level and study the impact and regulation of redox on these nuclear proteins’ functionality (which influence control mechanisms underpinning plant growth and stress tolerance).