The spatial organization of the cellular proteome is vital for cellular physiology, as protein localization is closely linked to post-translational modifications, subcellular trafficking, and protein-protein interactions. Systematic profiling of these spatial features can greatly enhance our understanding of protein functions. Recent advances in enzyme-mediated proximity labeling (PL) techniques, such as TurboID and APEX2, have improved our ability to map subcellular proteomes in living cells. This review discusses emerging trends in PL methods, which now offer subcellular precision with multi-dimensional protein features, including post-translational modifications, trafficking, turnover, and interaction with other biomolecules. Additionally, new techniques such as photoactivatable PL (optoPL) and antibody-targeted PL (immunoPL) provide enhanced spatiotemporal control and allow for detailed subcellular proteome mapping without genetic manipulation.
Wang et al. (2026) studied this question.