Structure Activity Relationship of USP5 Allosteric Inhibitors

Mann, M. K.; Zepeda-Velazquez, C. A.; Alvarez, H. G.; Dong, A.; Kiyota, T.; Aman, A.; Arrowsmith, C.; Al-Awar, R.; Harding, R. J.; Schapira, M.

doi:10.1101/2021.05.17.444542

bioRxiv · 10.1101/2021.05.17.444542

Structure Activity Relationship of USP5 Allosteric Inhibitors

Mann, M. K.·Zepeda-Velazquez, C. A.·Alvarez, H. G.·Dong, A.·Kiyota, T.·Aman, A.·Arrowsmith, C.·Al-Awar, R.·Harding, R. J.·Schapira, M.

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Abstract

USP5 is a deubiquitinase that has been implicated in a range of diseases, including cancer, but no USP5-targeting chemical probe has been reported to date. Here, we present the progression of a chemical series that occupies the C-terminal ubiquitin-binding site of a poorly characterized zinc-finger ubiquitin binding domain (ZnF-UBD) of USP5 and allosterically inhibits the catalytic activity of the enzyme. Systematic exploration of the structure-activity relationship, complemented with crystallographic characterization of the ZnF-UBD bound to multiple ligands, led to the identification of 64, which binds to the USP5 ZnF-UBD with a KD of 2.8 {micro}M. 64 is selective over the structurally similar ZnF-UBD domain of HDAC6 and inhibits USP5 catalytic activity in vitro with an IC50 of 26 {micro}M. This study provides a chemical and structural framework for the discovery of a chemical probe to delineate USP5 function in cells. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=86 SRC="FIGDIR/small/444542v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@3fc7bcorg.highwire.dtl.DTLVardef@15233e0org.highwire.dtl.DTLVardef@1cbf34corg.highwire.dtl.DTLVardef@d237d0_HPS_FORMAT_FIGEXP M_FIG Table of Contents Graphic C_FIG

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Mann, M. K., Zepeda-Velazquez, C. A., Alvarez, H. G., Dong, A., Kiyota, T., Aman, A., Arrowsmith, C., Al-Awar, R., Harding, R. J., Schapira, M.. 2021-05-18. Structure Activity Relationship of USP5 Allosteric Inhibitors. https://doi.org/10.1101/2021.05.17.444542

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