The lipid composition of biological membranes is key for cell viability. Nevertheless, and despite their central role in cell function, our understanding of membrane physiology continues to lag behind most other aspects of cell biology. The maintenance of membrane properties in situations of environmental stress requires homeostatic sense-and-response mechanisms. For example, the balance between esterified saturated (SFAs) and unsaturated fatty acids (UFAs), is a key factor determining lipid packing, water permeability, and membrane fluidity. The reduced thermal motion of lipid acyl chains triggered by an increase in SFAs causes a tighter lipid packing and increase the membrane viscosity. Conversely almost all organisms adapt to membrane rigidifying conditions, such as low temperature in poikilotherms, by incorporating more lipids with poorly packing unsaturated acyl chains. The molecular mechanisms underlying membrane homeostasis are only starting to emerge through combinations of genetics, cell biology, lipidomics, structural approaches and computational modelling. In this review we discuss recent advances in defining molecular machineries responsible for sensing membrane properties and mediating homeostatic responses in bacteria, yeast and animals. Although these organisms use remarkably distinct sensing mechanisms to mediate membrane adaptation, they suggest that the principle of transmembrane signaling to integrate membrane composition with lipid biosynthesis is ancient and essential for life.

生物膜的脂质组成是细胞活力的关键。尽管如此，尽管它们在细胞功能中起着中心作用，但我们对膜生理学的理解仍然落后于细胞生物学的大多数其他方面。在环境压力下维持膜性能需要稳态的感觉和反应机制。例如，酯化的饱和脂肪酸（SFA）和不饱和脂肪酸（UFA）之间的平衡是决定脂质堆积，水渗透性和膜流动性的关键因素。SFA增加引发的脂酰基链热运动降低，导致脂类堆积更加紧密，并增加了膜的粘度。相反，几乎所有生物都可以适应膜僵化条件，例如低温保温，通过掺入更多脂质，这些脂质具有不饱和的不饱和酰基链。膜稳态的分子机制只是通过遗传学，细胞生物学，脂质组学，结构方法和计算模型的结合才开始出现。在这篇综述中，我们讨论了在定义负责感知膜特性并介导细菌，酵母和动物体内稳态反应的分子机制方面的最新进展。尽管这些生物利用显着不同的传感机制来介导膜适应，但它们表明跨膜信号传导原理将膜成分与脂质生物合成整合在一起是古老的，对生命至关重要。细胞生物学，脂质组学，结构方法和计算模型。在这篇综述中，我们讨论了在定义负责感知膜特性并介导细菌，酵母和动物体内稳态反应的分子机制方面的最新进展。尽管这些生物利用显着不同的传感机制来介导膜适应，但它们表明跨膜信号传导原理将膜成分与脂质生物合成整合在一起是古老的，对生命至关重要。细胞生物学，脂质组学，结构方法和计算模型。在这篇综述中，我们讨论了在定义负责感知膜特性并介导细菌，酵母和动物体内稳态反应的分子机制方面的最新进展。尽管这些生物利用显着不同的传感机制来介导膜适应，但它们表明跨膜信号传导原理将膜成分与脂质生物合成整合在一起是古老的，对生命至关重要。