Specific fluorescence labeling of target proteins by using a ligand–4-azidophthalimide conjugate

Abstract

We herein propose a simple affinity-labeling method using a ligand–4-azidophthalimide (AzPI) conjugate. As a proof of concept, we show that two different ligand–AzPI conjugates enabled highly specific fluorescence labeling of their individual target proteins even in crude cell lysates. This method was also applied to label endogenous target proteins inside living cells.