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bioRxiv · 10.64898/2026.10.03.756418

Patronin condensation integrates recognition, protection and organization of microtubule minus ends

Zhang, B.·Yang, J.·Yu, S.·Zhou, K.·He, L.·Huang, L.·Liang, X.·Wang, H.·Chen, J.
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Abstract

Microtubule minus ends are central to non-centrosomal microtubule organization, yet how their recognition, protection and molecular organization are integrated remains unclear. Here we show that Drosophila Patronin forms dynamic condensates at microtubule minus ends through a prion-like domain (PrLD). PrLD-mediated condensation cooperates with the CKK domain and a second CKK-independent recognition region to convert weak or broadly distributed microtubule-binding activities into persistent minus-end recognition and tracking. Replacing the PrLD with a heterologous phase-separating HNRNPA1 IDR restores minus-end targeting, indicating that condensation capacity rather than PrLD primary sequence is critical. Patronin condensates further form a protective cap that resists minus-end depolymerization and recruit the cytoskeletal regulators Sas-4, Katanin and Ena. Disrupting PrLD multivalency impairs Patronin localization at multiple developmental sites and causes early organismal lethality. Thus, Patronin condensation creates a physiologically essential microtubule minus-end compartment coupling end recognition, stabilization and cytoskeletal organization.

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Zhang, B., Yang, J., Yu, S., Zhou, K., He, L., Huang, L., Liang, X., Wang, H., Chen, J.. 2026-10-06. Patronin condensation integrates recognition, protection and organization of microtubule minus ends. https://doi.org/10.64898/2026.10.03.756418

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