[SS02] Biophysics of cell and developmental biology

[SS02-05] Structure and fluctuation of biomolecular condensates in living cells

*Shunsuke F. Shimobayashi¹ (1. Kyoto University (Japan))

Keywords:

Liquid liquid phase separation

Liquid-liquid phase separation has been identified as a ubiquitous process in living cells, and is thought to drive the formation of dozens of intracellular structures, which represent condensed forms of biomolecular matter. However, we are still largely in the dark about when and where the condensates form, despite the critical link to their biological and pathological functions. Here, we demonstrate an optogenetics technology which can spatio-temporally control the condensate formation of intrinsically disordered proteins (IDPs) in nucleus and cytoplasm. By analyzing high-throughput data of condensate nucleation, we found that the formation process can be quantitatively interpreted within the framework of classical nucleation theory (CNT), which describes the nucleation process of water droplets from water vapor. Moreover, we quantitatively discuss how these condensation processes are templated with other organelles (e.g. genome, membranes, etc) in intracellular space. Our findings shed light on the structure and dynamics of the cooperative condensation principle from nuclear transcriptional condensates to synaptic condensates in neurons.References: Shimobayashi, S.F.. P. Ronceray, D. W. Sanders, M. P. Haataja, and C. P. Brangwynne, Nature, 599, 503-506 (2021).