Fractal avalanche ruptures in biological membranes
Fractal avalanche ruptures in biological membranes
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DOI：
10.1038/nmat2854
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发表时间：
2010-11-01
期刊：
影响因子：
41.2
通讯作者：
Orwar, Owe
中科院分区：
文献类型：
--
作者：
Gozen, Irep;Dommersnes, Paul;Orwar, Owe
双层膜包裹细胞和细胞器，并构成系统发育树所有分支中最普遍的生物材料。细胞膜破裂是一个重要的生物过程，在机械负荷下，骨骼肌和心肌细胞的破裂率很高(1)。细胞死亡等过程也可能诱发破裂(2)，而活跃的细胞膜修复机制对于保持细胞完整性至关重要(3)。细胞膜中的孔形成也是许多生物医学应用的核心，例如药物、基因和短干扰 RNA 递送 (4)。已研究了张应力下双层囊泡的膜破裂动力学(5-8)，其始终产生圆形孔(5,6)。我们观察到在固体支撑物上铺展的双层膜的破裂机制非常不同：在一个情况下，观察到指状不稳定性导致花状孔，而在另一个情况下，破裂以一系列快速崩塌进行，导致分形膜破碎。破裂演化的间歇性特征和雪崩尺寸的广泛分布与爆裂噪声动力学一致(9)。这种噪声动力学出现在固体无序材料的断裂(10)、塑性变形中的位错雪崩(11)和畴壁磁化雪崩(12)中。我们还在细胞膜扩散过程中观察到了类似的分形破裂力学。
Bilayer membranes envelope cells as well as organelles, and constitute the most ubiquitous biological material found in all branches of the phylogenetic tree. Cell membrane rupture is an important biological process, and substantial rupture rates are found in skeletal and cardiac muscle cells under a mechanical load(1). Rupture can also be induced by processes such as cell death(2), and active cell membrane repair mechanisms are essential to preserve cell integrity(3). Pore formation in cell membranes is also at the heart of many biomedical applications such as in drug, gene and short interfering RNA delivery(4). Membrane rupture dynamics has been studied in bilayer vesicles under tensile stress(5-8), which consistently produce circular pores(5,6). We observed very different rupture mechanics in bilayer membranes spreading on solid supports: in one instance fingering instabilities were seen resulting in floral-like pores and in another, the rupture proceeded in a series of rapid avalanches causing fractal membrane fragmentation. The intermittent character of rupture evolution and the broad distribution in avalanche sizes is consistent with crackling-noise dynamics(9). Such noisy dynamics appear in fracture of solid disordered materials(10), in dislocation avalanches in plastic deformations(11) and domain wall magnetization avalanches(12). We also observed similar fractal rupture mechanics in spreading cell membranes.