Membrane lipids diffuse rapidly in the plane of the membrane but their ability to flip spontaneously across a membrane bilayer is hampered by a significant energy barrier. Thus spontaneous flip-flop of polar lipids across membranes is very slow, even though it must occur rapidly to support diverse aspects of cellular life. Here we discuss the mechanisms by which rapid flip-flop occurs, and what role lipid flipping plays in membrane homeostasis and cell growth. We focus on conceptual aspects, highlighting mechanistic insights from biochemical and in silico experiments, and the recent, ground-breaking identification of a number of lipid scramblases.

中文翻译：

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脂质筋斗：揭示蛋白质介导的脂质翻转的机制

膜脂质在膜的平面内迅速扩散，但是它们自发地翻过膜双层的能力受到明显的能量屏障的阻碍。因此，极性脂质自发地穿过膜的自发翻转非常缓慢，即使它必须迅速发生以支持细胞生命的各个方面。在这里，我们讨论快速翻转发生的机制，以及脂质翻转在膜稳态和细胞生长中起什么作用。我们专注于概念方面，重点介绍了从生化和计算机模拟实验中获得的机械学见解，以及最近对许多脂质超标物进行的突破性鉴定。