Open AccessChemoproteomic Method for Profiling Inhibitor-Bound Kinase Complexes
Author(s) -
Linglan Fang,
Sujata Chakraborty,
Emily M. Dieter,
Zachary E. Potter,
Chloe K. Lombard,
Dustin J. Maly
Publication year - 2019
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.9b02963
Subject(s) - interactome , druggability , chemistry , protein–protein interaction , computational biology , kinase , proto oncogene tyrosine protein kinase src , microbiology and biotechnology , small molecule , plasma protein binding , drug discovery , proteomics , biochemistry , biology , gene
Small molecule inhibitors often only block a subset of the cellular functions of their protein targets. In many cases, how inhibiting only a portion of a multifunctional protein's functions affects the state of the cell is not well-understood. Therefore, tools that allow the systematic characterization of the cellular interactions that inhibitor-bound proteins make would be of great utility, especially for multifunctional proteins. Here, we describe a chemoproteomic strategy for interrogating the cellular localization and interactomes of inhibitor-bound kinases. By developing a set of orthogonal inhibitors that contain a trans -cyclooctene (TCO) click handle, we are able to enrich and characterize the proteins complexed to a drug-sensitized variant of the multidomain kinase Src. We show that Src's cellular interactions are highly influenced by the intermolecular accessibility of its regulatory domains, which can be allosterically modulated through its ATP-binding site. Furthermore, we find that the signaling status of the cell also has a large effect on Src's interactome. Finally, we demonstrate that our TCO-conjugated probes can be used as a part of a proximity ligation assay to study Src's localization and interactions in situ . Together, our chemoproteomic strategy represents a comprehensive method for studying the localization and interactomes of inhibitor-bound kinases and, potentially, other druggable protein targets.