Jin A J, Nossal R
Physical Sciences Laboratory, National Institutes of Health, Bethesda, Maryland 20892.
Biophys J. 1993 Oct;65(4):1523-37. doi: 10.1016/S0006-3495(93)81189-5.
By examining the basic characteristics of clathrin lattices, we discover that simple topological rules impose strict constraints on clathrin lattice transformations. These constraints require that internal bond rearrangements take place in conjunction with the addition or removal of pairs of clathrin triskelions within the interior of existing clathrin lattice patches. Similar constraints also are relevant to coated-vesicle shape changes and their budding-off from pit lattices. Via specific illustrations, successive vesicles with hexagonal-barrel and other coats are shown to grow out from the interior of a initially flat clathrin-coated pit so long as free triskelions are available from cytoplasm. Concomitantly, we present mathematical derivations of several simple and useful topological equations. These equations govern the numbers of nonhexagonal clathrin lattice facets and their variations during internal shape transformations and justify the proposed mechanisms of triskelion pair insertion and removal.
通过研究网格蛋白晶格的基本特征，我们发现简单的拓扑规则对网格蛋白晶格转变施加了严格的限制。这些限制要求在现有网格蛋白晶格片层内部添加或去除成对的网格蛋白三脚复合体时，内部键的重排要同时发生。类似的限制也与包被囊泡的形状变化及其从凹陷晶格上出芽有关。通过具体的例证表明，只要细胞质中有游离的三脚复合体，具有六边形桶状和其他包被的连续囊泡就会从最初平坦的网格蛋白包被凹陷内部生长出来。同时，我们给出了几个简单而有用的拓扑方程的数学推导。这些方程控制着非六边形网格蛋白晶格小面的数量及其在内部形状转变过程中的变化，并证明了所提出的三脚复合体对插入和去除机制的合理性。
