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bioRxiv · 10.1101/2023.01.07.522792

Passive endocytosis in protocells enables nutrient transport bypassing permeability limits

Zhang, S. J.·Anees, P.·Krishnan, Y.·Fai, T. G.·Szostak, J. W.·Wang, A.
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Abstract

Semipermeable membranes are a key feature of all living organisms. While specialized membrane transporters in cells can import otherwise impermeable nutrients, the earliest cells would have lacked a mechanism to import nutrients rapidly under nutrient-rich circumstances. Using both experiments and simulations, we find that a process akin to passive endocytosis can be recreated in model primitive cells. Molecules that are too impermeable to be absorbed can be taken up in a matter of seconds in an endocytic vesicle. The internalized cargo can then be slowly released over hours, into the main lumen or putative cytoplasm. This work demonstrates a way by which primitive life could have broken the symmetry of passive permeation prior to the evolution of protein transporters.

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Zhang, S. J., Anees, P., Krishnan, Y., Fai, T. G., Szostak, J. W., Wang, A.. 2023-01-07. Passive endocytosis in protocells enables nutrient transport bypassing permeability limits. https://doi.org/10.1101/2023.01.07.522792

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