Biophysical Society Thematic Meeting| Padova 2019

Quantitative Aspects of Membrane Fusion and Fission

Poster Abstracts

15-POS Board 15 STABILITY OF LD CONTACT SITE Laura J Endter 1 ; Herre Jelger Risselada 1 ;

1 Georg-August University, Theoretical Physics, Goettingen, Niedersachsen, Germany Lipid Droplets (LDs), although long time unterated in its role in eukaryotic cells, have now emerged to be extensively studied and still pose intriguing questions to the researchers engaged in unraveling their secrets. Being closely linked to regulatory processes regarding the lipid metabolism and homeostasis they are not only fascinating objects in a biophysical point of view but are also a possible target for medical applications for pathological conditions such as obesity and diabetes [1, 2].Once formed, the LD phospholipid monolayer appears to stay in close contact with the lipid bilayer of the endoplasmic reticulum. Aiming to determine the stability of the LD connection to the endoplasmic reticulum (ER) and the influence of seipin on that contact side we deploy coarse grained simulations using the Martini model. With calculations of free energy differences [3, 4] and barriers we may be able to shed some light on the question of the nature of the structure and the mechanistic pathway of formation and maintenance of the LD-ER contact site.[1] M. Schuldiner and M. Bohnert, Biochim. Biophys. Acta, Mol. Cell. Biol. Lipids, 1862, no. 10, 1188–1196 (2017).[2] A. R. Thiam and L. Fore^t, Biochim. Biophys. Acta, Mol. Cell. Biol. Lipids,1861, no. 8, 715–722 (2016).[3] Y. G. Smirnova, M. Fuhrmans, I . A. Barragan-Vidal, and M. Mu¨ller, J. Phys.D. Appl. Phys., 48, no. 34, 343001 (2015).[4] H. J. Risselada, Biophys. J., 112, no. 12, 2475–2478 (2017).

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