Abstract
Living cells are highly crowded with large and small biomolecules. The total concentration of biomolecules can reach 400 mg/ml, and 40% of the cell volume is occupied by biomolecules. Droplet formation in cells via liquid-liquid phase separation may play a role in controlling biochemical reactions in this complex molecular environment. Liquid-liquid phase separation generally involves nucleic acids and proteins as anionic and cationic components, respectively. Significant characteristics of droplets, which make them different from protein aggregation or fibril formation, are reversibility of formation and responsiveness to the molecular environment. In this review, we quantitatively describe the molecular environment inside cells and droplets that participate in controlling central dogma reactions. Finally, we discuss the importance of droplets under conditions of molecular crowding within living cells.
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This work was supported by JSPS KAKENHI (grant numbers 18K19153 and 17H06351 [Grant-in-Aid for Scientific Research on Innovative Areas “Chemistry for Multimolecular Crowding Biosystems])” and a research grant from the Asahi Glass Foundation, Japan.
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Kohata, K., Miyoshi, D. RNA phase separation–mediated direction of molecular trafficking under conditions of molecular crowding. Biophys Rev 12, 669–676 (2020). https://doi.org/10.1007/s12551-020-00696-3
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DOI: https://doi.org/10.1007/s12551-020-00696-3