Effective Tubulin Degradation by Rationally Designed Proteolysis Targeting Chimeras

Maiocchi, A.; Abel, A.-C.; Basellini, M.; Perez-Pena, H.; Boiarska, Z.; Ferrandi, E. E.; Kozicka, Z.; Fasano, V.; Pieraccini, S.; Cappelletti, G.; Steinmetz, M. O.; Passarella, D.; Prota, A. E.

doi:10.1101/2025.05.22.655572

bioRxiv · 10.1101/2025.05.22.655572

Effective Tubulin Degradation by Rationally Designed Proteolysis Targeting Chimeras

Maiocchi, A.·Abel, A.-C.·Basellini, M.·Perez-Pena, H.·Boiarska, Z.·Ferrandi, E. E.·Kozicka, Z.·Fasano, V.·Pieraccini, S.·Cappelletti, G.·Steinmetz, M. O.·Passarella, D.·Prota, A. E.

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Abstract

Proteolysis targeting chimeras (PROTACs) are heterobifunctional molecules that induce the degradation of proteins of interest (POIs) via the ubiquitin-proteasome pathway by recruiting E3 ligases to form a ternary complex with the POI. In this study, we rationally designed and synthesized PROTACs targeting the {beta}-tubulin heterodimer, the building block of microtubules (MTs) that are essential for numerous cellular functions and represent important therapeutic targets in cancer and neurodegenerative diseases. Maytansinol, a known MT-destabilising agent, was selected as the POI ligand, functionalised and conjugated to linkers bearing cereblon or Von Hippel-Lindau ligands as E3 ligase recruiters. Four compounds were synthesized and characterized through structural, biophysical and cell biology studies to evaluate their ability to form degradation-prone tubulin-PROTAC-E3 ligase ternary complexes. We confirmed that the PROTACs effectively bind tubulin and recruit E3 ligases. Remarkably, two PROTACs exhibited cellular degradation activity, representing an important advancement in chemically inducing tubulin-E3-ligase interactions. This work integrates rational design, biophysical and structural validation, and cell-based studies to establish a robust framework for developing tubulin-targeting PROTACs, offering significant implications for basic research and therapeutic developments.

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Maiocchi, A., Abel, A.-C., Basellini, M., Perez-Pena, H., Boiarska, Z., Ferrandi, E. E., Kozicka, Z., Fasano, V., Pieraccini, S., Cappelletti, G., Steinmetz, M. O., Passarella, D., Prota, A. E.. 2025-05-25. Effective Tubulin Degradation by Rationally Designed Proteolysis Targeting Chimeras. https://doi.org/10.1101/2025.05.22.655572

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