9f81
Crystal structure of RIOK2 with a covalent compound GCL 47
Structural highlights
FunctionRIOK2_HUMAN Serine/threonine-protein kinase involved in the final steps of cytoplasmic maturation of the 40S ribosomal subunit. Involved in export of the 40S pre-ribosome particles (pre-40S) from the nucleus to the cytoplasm. Its kinase activity is required for the release of NOB1, PNO1 and LTV1 from the late pre-40S and the processing of 18S-E pre-rRNA to the mature 18S rRNA (PubMed:19564402). Regulates the timing of the metaphase-anaphase transition during mitotic progression, and its phosphorylation, most likely by PLK1, regulates this function (PubMed:21880710).[1] [2] [3] Publication Abstract from PubMedProtein kinases are important drug targets, yet specific inhibitors have been developed for only a fraction of the more than 500 human kinases. A major challenge in designing inhibitors for highly related kinases is selectivity. Unlike their non-covalent counterparts, covalent inhibitors offer the advantage of selectively targeting structurally similar kinases by modifying specific protein side chains, particularly non-conserved cysteines. Previously, covalent fragment screens yielded potent and selective compounds for individual kinases such as ERK1/2 but have not been applied to the broader kinome. Furthermore, many of the accessible cysteine positions have not been addressed so far. Here, we outline a generalizable approach to sample ATP-site cysteines with fragment-like covalent inhibitors. We present the development of a kinase-focused fragment library and its systematic screening against a curated selection of 47 kinases, with 60 active site-proximal cysteines using LC/MS and differential scanning fluorimetry (DSF) assays, followed by hit validation through various complementary techniques. Our findings expand the repertoire of targetable cysteines within protein kinases, provide insight into unique binding modes identified from crystal structures and deliver isoform-specific hits with promising profiles as starting points for the development of highly potent and selective covalent inhibitors. Probing the Protein Kinases' Cysteinome by Covalent Fragments.,Wang G, Seidler NJ, Rohm S, Pan Y, Liang XJ, Haarer L, Berger BT, Sivashanmugam SA, Wydra VR, Forster M, Laufer SA, Chaikuad A, Gehringer M, Knapp S Angew Chem Int Ed Engl. 2024 Dec 24:e202419736. doi: 10.1002/anie.202419736. PMID:39716901[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
