Proximity-Ligation Assay to Detect Peroxisome-Organelle Interaction

Peroxisomes are essential organelles in mammals, which contribute to cellular lipid metabolism and redox homeostasis. They do not function as isolated entities but cooperate and interact with other subcellular organelles, in particular the endoplasmic reticulum, mitochondria, and lipid droplets. Those interactions are often mediated by membrane contact sites. Tether proteins at those sites bring the organelles in close proximity to facilitate metabolite and lipid transfer as well as organelle communication. There is great interest in the investigation of the physiological functions of peroxisome-organelle contacts and how they are regulated. Here, we present an antibody- and fluorescence-based proximity ligation approach used successfully in our laboratory for the detection and quantification of peroxisome-organelle interactions in cultured mammalian cells.