In plants as well as other organisms, protein localization alone is insufficient to provide a mechanistic link between stimulus and process regulation. This is because protein-protein interactions are central to the regulation of biological processes. However, they remain very difficult to detect in situ, with the choice of tools for the detection of protein-protein interaction in situ still in need of expansion. Here, we provide a protocol for the detection and accurate localization of protein interactions based on the combination of a whole-mount proximity ligation assay and iRoCS, a coordinate system able to standardize subtle differences between the architecture of individual Arabidopsis roots.
Keywords: 3D imaging; Arabidopsis thaliana; In planta; In situ; Protein complex; Protein–protein interactions; Proximity ligation assay; Root apical meristem; iRoCS.