As early as the development of the fluid mosaic model for cellular membranes, researchers began observing the telltale signs of lateral heterogeneity. Over the decades this has led to the development of the lipid raft hypothesis and the ensuing controversy that has unfolded, as a result. Here, we review the physical concepts behind domain formation in lipid membranes, both of their structural and dynamic origins. This, then leads into a discussion of coarse-grained, phenomenological approaches that describe the wide range of phases associated with lipid lateral heterogeneity. We use these physical concepts to describe the interaction between raft-lipid species, such as long-chain saturated lipids, sphingomyelin, and cholesterol, and non-raft forming lipids, such as those with short acyl chains or unsaturated fatty acids. While debate has persisted on the biological relevance of lipid domains, recent research, described here, continues to identify biological roles for rafts and new experimental approaches have revealed the existence of lipid domains in living systems. Given the recent progress on both the biological and structural aspects of raft formation, the research area of membrane lateral heterogeneity will not only expand, but will continue to produce exciting results.

早在细胞膜流体镶嵌模型开发出来时，研究人员就开始观察横向异质性的迹象。几十年来，这导致了脂筏假说的发展以及随之而来的争议。在这里，我们回顾了脂质膜域形成背后的物理概念，包括它们的结构和动态起源。然后，这引发了对粗粒度现象学方法的讨论，这些方法描述了与脂质横向异质性相关的广泛阶段。我们使用这些物理概念来描述筏脂质种类（例如长链饱和脂质、鞘磷脂和胆固醇）与非筏形成脂质（例如具有短酰基链或不饱和脂肪酸的脂质）之间的相互作用。虽然关于脂质结构域的生物学相关性的争论一直存在，但此处描述的最新研究继续确定筏的生物学作用，并且新的实验方法揭示了生命系统中脂质结构域的存在。鉴于筏形成的生物学和结构方面的最新进展，膜横向异质性的研究领域不仅会扩大，而且将继续产生令人兴奋的结果。