Biophysical Society Conference | Estes Park 2023

Membrane Budding and Fusion

Poster Abstracts

20-POS Board 7 MEMBRANE DYNAMICS CONTROL FUSION, FISSION AND PATTERNING

David V. Svintradze 1 ; 1 New Vision University, School of Medicine, Tbilisi, Georgia

The Young-Laplace, Kelvin and Gibbs-Thomson equations explain chemical potential dependence on curvature factors of the condensates, therefore it is apriori assumed that these laws explain the physics behind condensation and or phase separation. However, the laws are formulated only for basic (sphere, cylinder, plane) and static geometries and their applicability for arbitrarily curved and shape-changing condensates is largely incorrect. Therefore, the consequent phenomenon which is Ostwald ripening is also producing only very limited and not true for living systems prediction. Namely, according to Ostwald ripening large condensates are energetically more favorable than small ones, therefore small particles dissolve and redeposit on large ones. As a result, large condensates get larger at the expanse of smaller ones, this phenomenon is known as Ostwald ripening. However, the phenomenon does not take into account the dynamic curvature effects of condensates shapes, so its general applicability, as well as the conclusion, is questionable for dynamically curving and largely deviating from sphere condensates. We have generalized the Young-Laplace, Kelvin and Gibbs-Thomson concepts and revised Ostwald ripening phenomena for non-equilibrium shape-changing condensates and have shown with mathematical rigor that, shape dynamics might induce fission, fusion, and formation of membrane-like structure on the surface of condensates and its patterning (Svintradze, Biophysical Journal 122: 892-904, 2023). This statement is generally true for any interface, therefore it is also applicable to membrane dynamics. Consequently one can directly claim that membrane dynamics controls fusion, fission and pattern formation.

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