An update of label-free protein target identification methods for natural active products

Abstract

Natural active products (NAPs) are derived from chemical substances found in nature that have biological activity and medicinal potential. Screening and revealing the protein targets of NAPs is an indispensable link in the pharmacological and toxicological understanding of NAPs. Proteins are the main factors executing cell functions, and cells rely on the function of proteins to complete various activities in the life cycle. The important mechanism of action of drugs is to regulate cell biological activities by interacting with proteins and other macromolecules. At present, the classic way to screen protein targets is based on the molecular label tracing method, which has a long cycle and changes the molecular structure and pharmacological effects of NAPs. Due to the shortcomings of molecular labelling methods, in recent years, scientists have tried to develop a variety of label-free protein target identification methods for NAPs and have made a certain amount of progress. This article reviews the current protein target identification methods for NAPs with the aim of providing a reference for research on NAP protein targets.

Trans-(±)-Kusunokinin Binding to AKR1B1 Inhibits Oxidative Stress and Proteins Involved in Migration in Aggressive Breast Cancer

“…Therefore, in this study, ( )KU was investigated for its direct target binding on AKR1B1 using the cellular thermal shift assay (CETSA). This technique is a label-free protein target identification strategy for active compounds that evaluate the engagement of drug and target proteins in the cells [ 28 ]. Previously, CETSA was performed in order to investigate molecular targets related to the antiosteoporosis effects of 9′-O-di-(E)-feruloyl-meso-5, 5′-dimethoxysecoisolariciresinol, a lignan isolated from Litsea cubeba , which revealed potential binding activities to cathepsin K and MEK1 [ 29 ].…”

Target identification of small molecules: an overview of the current applications in drug discovery

“…Although this approach avoids any potential problems associated with compound labelling, it has few limitations as this label-free molecule can bind to unintended proteins and result in identification of false positive targets [ 99 , 108 ]. Furthermore, this method is not suitable for proteins that are only expressed at low levels [ 6 , 99 ]. Below, we will review a few examples of adopting this approach and discuss these limitations in detail (Fig.…”

Small-molecule probes from bench to bedside: advancing molecular analysis of drug–target interactions toward precision medicine

“…27,28 Label-free approaches are also being developed to measure changes in the thermal, proteolytic, or chemical stability of drug-bound target complexes. 29 Due to the subtle and non-specific nature of druginduced changes, these approaches are often coupled with isobaric labeling and tandem mass spectrometry to improve the overall detection sensitivity and target coverage.…”