Kumarage Teshani, Gupta Sudipta, Morris Nicholas B, Doole Fathima T, Scott Haden L, Stingaciu Laura-Roxana, Pingali Sai Venkatesh, Katsaras John, Khelashvili George, Doktorova Milka, Brown Michael F, Ashkar Rana
Department of Physics, Virginia Tech, Blacksburg, VA, USA.
Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, USA.
Nat Commun. 2025 Jul 31;16(1):7024. doi: 10.1038/s41467-025-62106-0.
Cholesterol and lipid unsaturation underlie a balance of opposing forces that features prominently in adaptive cell responses to diet and environmental cues. These competing factors have resulted in contradictory observations of membrane elasticity across different measurement scales, requiring chemical specificity to explain incompatible structural and elastic effects. Here, we demonstrate that - unlike macroscopic observations - lipid membranes exhibit a unified elastic behavior in the mesoscopic regime between molecular and macroscopic dimensions. Using nuclear spin techniques and computational analysis, we find that mesoscopic bending moduli follow a universal dependence on the lipid packing density regardless of cholesterol content, lipid unsaturation, or temperature. Our observations reveal that compositional complexity can be explained by simple biophysical laws that directly map membrane elasticity to molecular packing associated with biological function, curvature transformations, and protein interactions. The obtained scaling laws closely align with theoretical predictions based on conformational chain entropy and elastic stress fields. These findings provide unique insights into the membrane design rules optimized by nature and unlock predictive capabilities for guiding the functional performance of lipid-based materials in synthetic biology and real-world applications.
胆固醇和脂质不饱和度构成了一种相反作用力的平衡，这在细胞对饮食和环境线索的适应性反应中显著体现。这些相互竞争的因素导致了在不同测量尺度下对膜弹性的矛盾观察结果，需要化学特异性来解释不相容的结构和弹性效应。在这里，我们证明，与宏观观察结果不同，脂质膜在分子尺寸和宏观尺寸之间的介观尺度上表现出统一的弹性行为。利用核自旋技术和计算分析，我们发现介观弯曲模量普遍依赖于脂质堆积密度，而与胆固醇含量、脂质不饱和度或温度无关。我们的观察结果表明，组成复杂性可以用简单的生物物理定律来解释，这些定律直接将膜弹性与与生物功能、曲率转变和蛋白质相互作用相关的分子堆积联系起来。所获得的标度定律与基于构象链熵和弹性应力场的理论预测紧密一致。这些发现为自然优化的膜设计规则提供了独特的见解，并为指导合成生物学和实际应用中基于脂质的材料的功能性能开启了预测能力。
