Protein interactome mapping in .

The systematic identification of all protein-protein interactions that take place in an organism (the 'interactome') is an important goal in modern biology. The nematode was one of the first multicellular models for which a proteome-wide interactome mapping project was initiated. Most interactome mapping efforts have utilized the yeast two-hybrid system, yielding an extensive binary interactome, while recent developments in mass spectrometry-based approaches hold great potential for further improving our understanding of protein interactome networks in a multicellular context. For example, methods like co-fractionation, proximity labeling, and tissue-specific protein purification not only identify protein-protein interactions, but have the potential to provide crucial insight into when and where interactions take place. Here we review current standards and recent improvements in protein interaction mapping in