Biophysical and biochemical properties of Deup1 self-assemblies: A potential driver for deuterosome formation during multiciliogenesis

Abstract

The deuterosome is a non-membranous organelle involved in largescale centriole amplification during multiciliogenesis. Deuterosomes are specifically assembled during the process ofmulticiliogenesis. However, the molecular mechanisms underlying deuterosome formation are poorly understood. In this study, we investigated the molecular properties of deuterosome protein 1 (Deup1), an essential protein involved in deuterosome assembly.We found that Deup1 has the ability to self-assemble into macromolecular condensates both in vitro and in cells. The Deup1-containing structures formed in multiciliogenesis and the Deup1 condensates self-assembled in vitro showed low turnover of Deup1, suggesting that Deup1 forms highly stable structures. Our biochemical analyses revealed that an increase of the concentration of Deup1 and a crowded molecular environment both facilitate Deup1 selfassembly. The self-assembly of Deup1 relies on its N-terminal region, which contains multiple coiled coil domains. Using an optogenetic approach,we demonstrated that self-assembly and theC-terminal half of Deup1 were sufficient to spatially compartmentalize centrosomal protein 152 (Cep152) and polo like kinase 4 (Plk4), master components for centriole biogenesis, in the cytoplasm. Collectively, the present data suggest thatDeup1 forms the structural core of the deuterosome through self-assembly into stable macromolecular condensates.