生物立方膜

Biological Cubic Membranes

脂质立方液晶在药物载体方面有着较为广泛的应用.然而在生物体内,有一种与之类似的结构,称为立方膜.具体而言,立方膜就是指含有脂蛋白的三维周期性脂质双分子单层、双层或多层的纳米曲面结构.亚细胞器中的这种生物立方膜结构可能也能作为药物载体,同时有抗氧化、紫外滤光等潜在作用.本文将主要介绍立方膜的研究进展、形成机理,以及在自然界中的存在情况,及其功能和潜在的应用价值.

Biomembranes play fundamental roles in all living systems to partition cells into subcellular compartments. However, these typically fiat membranes may also fold into 3D periodic nanostructures, termed cubic membranes （CM）, under certain physiological or pathological conditions. Three types of CM arrangements-- gyroid （G）, double diamond （D） and primitive （P）--have been identified in multiple cell types, yet their biological function is still obscure. The surfaces describing CM are triply periodic minimal or level surfaces and of great technological potential in crystalline and liquid crystalline materials at various length scales. This review briefly introduces： （1） the characterization of CM nanostructures by transmission electron microscope （TEM）, scanning electron microscope （SEM） and EM tomography in biological systems; （2） an update on experimental data describing the role of lipids, proteins and Ca2＋ on CM formation; （3） the proposed optical and antioxidant properties of CM; （4） the potential applications as a diagnostic biomarker for various human diseases, use of CM-derived lipids as gene delivery vehicles, use of CM as structural antioxidant, and CM-based photonic crystals as versatile light-modulators.