Proximity labeling: an emerging tool for probing in planta molecular interactions

Protein–protein interaction(PPI)networks are key to nearly all aspects of cellular activity.Therefore,the identification of PPIs is important for understanding a specific biological process in an organism.Compared with conventional methods for probing PPIs,the recently described proximity labeling(PL)approach combined with mass spectrometry(MS)-based quantitative proteomics hasemerged as apowerful approach for characterizing PPIs.However,the application of PL in planta remains in its infancy.Here,we summarize recent progress in PL and its potential utilization in plant biology.We specifically summarize advances in PL,including the development and comparison of different PL enzymes and the application of PL for deciphering various molecular interactions in different organisms with an emphasis on plant systems.