Akabas M H, Cohen F S, Finkelstein A
J Cell Biol. 1984 Mar;98(3):1063-71. doi: 10.1083/jcb.98.3.1063.
We demonstrate that there are two experimentally distinguishable steps in the fusion of phospholipid vesicles with planar bilayer membranes. In the first step, the vesicles form a stable, tightly bound pre-fusion state with the planar membrane; divalent cations (Ca++) are required for the formation of this state if the vesicular and/or planar membrane contain negatively charged lipids. In the second step, the actual fusion of vesicular and planar membranes occurs. The driving force for this step is the osmotic swelling of vesicles attached (in the pre-fusion state) to the planar membrane. We suggest that osmotic swelling of vesicles may also be crucial for biological fusion and exocytosis.
我们证明,磷脂囊泡与平面双层膜融合过程中有两个实验上可区分的步骤。第一步,囊泡与平面膜形成稳定、紧密结合的预融合状态;如果囊泡膜和/或平面膜含有带负电荷的脂质,形成这种状态需要二价阳离子(Ca++)。第二步,囊泡膜与平面膜发生实际融合。这一步的驱动力是附着(处于预融合状态)在平面膜上的囊泡的渗透膨胀。我们认为,囊泡的渗透膨胀对于生物融合和胞吐作用可能也至关重要。