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bioRxiv · 10.64898/2026.01.09.698636

Organelle biogenesis on a synthetic bead

Chang, C.-C.·Peng, M.·Blaya-Martinez, L.·Wong, S.-S.·Mohamad, N.·Xiao, B.·Monteiro, J. M.·Harrison, T.·Raff, J. W.
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Abstract

How cells build their many organelles remains poorly understood. Centrosomes are a striking example: structurally complex organelles built from more than one hundred different proteins. Here we show that a synthetic bead can generate centrosome-like particles (CLiPs) in early Drosophila embryos if it is programmed to recruit any one of five essential centrosome assembly proteins. CLiPs behave remarkably like centrosomes: organising centrosomal proteins, microtubules and actomyosin, forming spindle poles, and undergoing multiple rounds of duplication - all in synchrony with the embryonic cell cycle. The beads generate CLiPs because they recruit Plk4, the master regulator of centrosome biogenesis, in a specific manner that stimulates its assembly activity. Thus, recruiting a single protein to a synthetic surface is sufficient to seed the self-assembly of a complex, self-propagating entity. These findings suggest a general framework for organelle biogenesis in which simple localised molecular inputs can seed the self-assembly of highly complex cellular structures.

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Chang, C.-C., Peng, M., Blaya-Martinez, L., Wong, S.-S., Mohamad, N., Xiao, B., Monteiro, J. M., Harrison, T., Raff, J. W.. 2026-01-12. Organelle biogenesis on a synthetic bead. https://doi.org/10.64898/2026.01.09.698636

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