Selective inhibition reveals the regulatory function of DYRK2 in protein synthesis and calcium entry

Lei, X.; Wei, T.; Wang, J.; Liang, R.; Chen, W.; He, A.; Du, Y.; Zhou, W.; Zhang, Z.; Ma, M.; Lu, J.; Guo, X.; Chen, X.; Tian, R.; Xiao, J.

doi:10.1101/2021.02.12.430909

bioRxiv · 10.1101/2021.02.12.430909

Selective inhibition reveals the regulatory function of DYRK2 in protein synthesis and calcium entry

Lei, X.·Wei, T.·Wang, J.·Liang, R.·Chen, W.·He, A.·Du, Y.·Zhou, W.·Zhang, Z.·Ma, M.·Lu, J.·Guo, X.·Chen, X.·Tian, R.·Xiao, J.

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Abstract

The dual-specificity tyrosine phosphorylation-regulated kinase DYRK2 has emerged as a key regulator of cellular processes such as proteasome-mediated protein degradation. To gain further insights into its function, we took a chemical biology approach and developed C17, a potent small-molecule DYRK2 inhibitor, through multiple rounds of structure-based optimization guided by a number of co-crystallized structures. C17 displayed an effect on DYRK2 at a single-digit nanomolar IC50 and showed outstanding selectivity for the human kinome containing 467 other human kinases. Using C17 as a chemical probe, we further performed quantitative phosphoproteomic assays and identified several novel DYRK2 targets, including eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) and stromal interaction molecule 1 (STIM1). DYRK2 phosphorylated 4E-BP1 at multiple sites, and the combined treatment of C17 with AKT and MEK inhibitors showed synergistic 4E-BP1 phosphorylation suppression. The phosphorylation of STIM1 by DYRK2 substantially increased the interaction of STIM1 with the ORAI1 channel, and C17 impeded the store-operated calcium entry process. Collectively, these studies further expand our understanding of DYRK2 and provide a valuable tool to further pinpoint its biological function.

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Lei, X., Wei, T., Wang, J., Liang, R., Chen, W., He, A., Du, Y., Zhou, W., Zhang, Z., Ma, M., Lu, J., Guo, X., Chen, X., Tian, R., Xiao, J.. 2021-02-12. Selective inhibition reveals the regulatory function of DYRK2 in protein synthesis and calcium entry. https://doi.org/10.1101/2021.02.12.430909

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