Clathrin-mediated endocytosis is one of the major pathways by which cells internalise cargo molecules. Recently it has been shown that clathrin triskelia can first assemble as flat lattices before the membrane starts to bend. However, for fully assembled clathrin lattices high energetic and topological barriers exist for the flat-to-curved transition. Here we explore the possibility that flat clathrin lattices grow with vacancies that are not visible in traditional imaging techniques but would lower these barriers. We identify the Eden model for cluster growth as the most appropriate modeling framework and systematically derive the four possible variants that result from the specific architecture of the clathrin triskelion. Our computer simulations show that the different models lead to clear differences in the statistical distributions of cluster shapes and densities. Experimental results from electron microscopy and correlative light microscopy provide first indications for the model variants with a moderate level of lattice vacancies.

网格蛋白介导的内吞作用是细胞内化货物分子的主要途径之一。最近已经表明网格蛋白 triskelia 可以在膜开始弯曲之前首先组装成扁平的晶格。然而，对于完全组装的网格蛋白晶格，平面到弯曲的过渡存在高能量和拓扑障碍。在这里，我们探讨了平面网格蛋白晶格生长的可能性，这些空位在传统成像技术中是不可见的，但会降低这些障碍。我们将集群增长的 Eden 模型确定为最合适的建模框架，并系统地推导出由网格蛋白 triskelion 的特定架构产生的四种可能的变体。我们的计算机模拟表明，不同的模型导致集群形状和密度的统计分布存在明显差异。电子显微镜和相关光学显微镜的实验结果为具有中等晶格空位水平的模型变体提供了初步迹象。