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A Simple, Robust, and High Throughput Single Molecule Flow Stretching Assay Implementation for Studying Transport of Molecules Along DNA
Published on: October 1, 2017
Non-Fickian Molecular Transport in Protein-DNA Droplets
1Center for Soft and Living Matter, Institute for Basic Science, Ulsan 44919, Republic of Korea.
Abstract:
Bulk-level measurements of dynamics have suggested that phase-separated, protein-nucleic acid rich droplets can be viewed as simple liquids. In this report, we show that histone proteins spontaneously phase separate into liquid-like droplets in the presence of DNA. Using super-resolution fluorescence microscopy, we find that molecular transport in these droplets is non-Fickian (subdiffusive) at nanoscopic length scales. This observation cannot be explained by charge-charge interactions. Instead, our results strongly suggest that cation-π interactions drive the non-Fickian behavior. Given the ubiquity of cationic and aromatic moieties in protein-nucleic acid rich liquid-like phases observed in cells, we anticipate that non-Fickian diffusion is a general transport mechanism in such phases.
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