Waeterschoot Jorik, Barniol-Xicota Marta, Verhelst Steven, Baatsen Pieter, Koos Erin, Lammertyn Jeroen, Casadevall I Solvas Xavier
Biomimetics Group, Division of Mechatronics, Biostatistics and Sensors (MeBios), Department of Biosystems, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
Department of Medicine and Life Sciences (MELIS), Barcelona Biomedical Research Park, Universitat Pompeu Fabra, Carrer Dr. Aiguader 88, 08003 Barcelona, Spain.
Heliyon. 2024 Sep 18;10(18):e37915. doi: 10.1016/j.heliyon.2024.e37915. eCollection 2024 Sep 30.
Understanding the intricate functions of membrane proteins is pivotal in cell biology and drug discovery. The composition of the cell membrane is highly complex, with different types of membrane proteins and lipid species. Hence, studying cellular membranes in a complexity-reduced context is important to enhance our understanding of the roles of these different elements. However, reconstitution of membrane proteins in an environment that closely mimics the cell, like giant unilamellar vesicles (GUVs), remains challenging, often requiring detergents that compromise protein function. To address this challenge, we present a novel strategy to manufacture GUVs from styrene maleic acid lipid particles (SMALPs) that utilises surfactant-stabilised droplets as a template. As a first step towards the incorporation of membrane proteins, this work focusses on the conversion of pure lipid SMALPs in GUVs. To evaluate the method, we produced a new form of SMA linked to fluorescein, referred to as FSMA. We demonstrate the assembly of SMALPs at the surfactant-stabilised droplet interface, resulting in the formation of GUVs when released upon addition of a demulsifying agent. The released vesicles appear similar to electroformed vesicles imaged with confocal light microscopy, but a fluorescein leakage assay and cryo-TEM imaging reveal their porous nature, potentially as a result of residual interactions of SMA with the lipid bilayer. Our study represents a significant step towards opening new avenues for comprehensive protein research in a complexity-reduced, yet biologically relevant, setting.
了解膜蛋白的复杂功能在细胞生物学和药物发现中至关重要。细胞膜的组成高度复杂，包含不同类型的膜蛋白和脂质种类。因此，在简化复杂性的背景下研究细胞膜对于增进我们对这些不同元素作用的理解很重要。然而，在像巨型单层囊泡（GUVs）这样紧密模拟细胞的环境中重组膜蛋白仍然具有挑战性，通常需要使用会损害蛋白质功能的去污剂。为应对这一挑战，我们提出了一种从苯乙烯马来酸脂质颗粒（SMALPs）制造GUVs的新策略，该策略利用表面活性剂稳定的液滴作为模板。作为将膜蛋白整合的第一步，这项工作聚焦于将纯脂质SMALPs转化为GUVs。为评估该方法，我们制备了一种与荧光素相连的新型SMA形式，称为FSMA。我们展示了SMALPs在表面活性剂稳定的液滴界面处的组装，当加入破乳剂后释放时会形成GUVs。释放的囊泡看起来与用共聚焦光学显微镜成像的电铸囊泡相似，但荧光素泄漏测定和冷冻透射电子显微镜成像揭示了它们的多孔性质，这可能是由于SMA与脂质双层的残余相互作用导致的。我们的研究朝着在简化复杂性但具有生物学相关性的环境中为全面的蛋白质研究开辟新途径迈出了重要一步。
