Two timescales control the creation of large protein aggregates in cells.

Biophys J

Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR 168, Paris, France; Sorbonne Universités, UPMC University Paris 06, Paris, France. Electronic address:

Published: June 2021

Protein aggregation is of particular interest because of its connection with many diseases and disorders. Many factors can alter the dynamics and result of this process, one of them being the diffusivity of the monomers and aggregates in the system. Here, we study experimentally and theoretically an aggregation process in cells, and we identify two distinct physical timescales that set the number and size of aggregates. The first timescale involves fast aggregation of small clusters freely diffusing in the cytoplasm, whereas in the second one, the aggregates are larger than the pore size of the cytoplasm and thus barely diffuse, and the aggregation process is slowed down. However, the process is not entirely halted, potentially reflecting a myriad of active but random forces that stir the aggregates. Such a slow timescale is essential to account for the experimental results of the aggregation process. These results could also have implications in other processes of spatial organization in cell biology, such as phase-separated droplets.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8392093PMC
http://dx.doi.org/10.1016/j.bpj.2021.04.032DOI Listing

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