Reagents for Detecting Phosphosites within Proteins

Protein phosphorylation is an important post-translational modification [PTM] that cells employ to coordinate diverse biological processes. In the past, antibodies have been used as tools for studying phosphosites within proteins, but due to intrinsic limitations with their production and validation, scientists are now turning to other options. Two types of new reagents have recently emerged as attractive alternatives for monitoring phosphosites: polymers [ie, pIMAGO, Phos-tag] and recombinant affinity reagents [ie, DARPINs, FHA domain, FN3, scFv]. Both types of reagents can be used in ELISA, western blotting, and cell staining experiments to detect phosphorylated proteins. This mini-review focuses on the development and utility of each of their agents for detecting phosphosites and examines their strengths and weaknesses.