title: Activity-based probes for protein tyrosine phosphatases.
abstract: Protein tyrosine phosphatases (PTPs) are involved in the regulation of many aspects of cellular activity including proliferation, differentiation, metabolism, migration, and survival. Given the large number and complexity of PTPs in cell signaling, new strategies are needed for the integrated analysis of PTPs in the whole proteome. Unfortunately, the activities of many PTPs are tightly regulated by posttranslational mechanisms, limiting the utility of standard genomics and proteomics methods for functional characterization of these enzymes. To facilitate the global analysis of PTPs, we designed and synthesized two activity-based probes that consist of alpha-bromobenzylphosphonate as a PTP-specific trapping device and a linker that connects the trapping device with a biotin tag for visualization and purification. We showed that these probes are active site-directed irreversible inactivators of PTPs and form a covalent adduct with PTPs involving the active site Cys residue. Additionally, we demonstrated that the probes are extremely specific toward PTPs while remaining inert to other proteins, including the whole proteome from Escherichia coli. Consequently, these activity-based PTP probes can be used to profile PTP activity in complex proteomes. The ability to interrogate the entire PTP family on the basis of changes in their activity should greatly accelerate both the assignment of PTP function and the identification of potential therapeutic targets.
authors.affiliation: Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: Sanjai
authors.initials: S
authors.lastname: Kumar
authors.forename: Bo
authors.initials: B
authors.lastname: Zhou
authors.forename: Fubo
authors.initials: F
authors.lastname: Liang
authors.forename: Wei-Qing
authors.initials: WQ
authors.lastname: Wang
authors.forename: Zhonghui
authors.initials: Z
authors.lastname: Huang
authors.forename: Zhong-Yin
authors.initials: ZY
authors.lastname: Zhang
mesh_terms: D001665:Binding Sites; D019921:Biotinylation; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D015335:Molecular Probes / Q000737:chemistry* / Q000378:metabolism*; D015394:Molecular Structure; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D012680:Sensitivity and Specificity; D013379:Substrate Specificity
chemical_list: D015335:Molecular Probes; D020543:Proteome; D017027:Protein Tyrosine Phosphatases