Hierarchical assembly is more robust than egalitarian assembly in synthetic capsids.
Hierarchical assembly is more robust than egalitarian assembly in synthetic capsids.
复制标题
合成衣壳中的分层组装比平等组装更稳健。
DOI：
10.1073/pnas.2312775121
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发表时间：
2024
影响因子：
11.1
通讯作者：
Fraden,Seth
中科院分区：
文献类型：
--
作者：
Wei,Wei-Shao;Trubiano,Anthony;Sigl,Christian;Paquay,Stefan;Dietz,Hendrik;Hagan,MichaelF;Fraden,Seth
复杂功能材料的自组装一直是软材料科学的一大挑战。有效的组装取决于热力学和动力学效应之间的微妙平衡，需要微调亲和力和亚基浓度。相比之下，我们引入了一种装配范式，该范式允许在亚基亲和力中具有较大的容错能力，并有助于避免动力学陷阱。我们的结合实验和计算方法使用了一个三角形亚基的模型系统，该系统被编程组装成包含60个单元的t = 3个二十面体衣壳。实验平台使用DNA折纸技术来制造单分散胶体，其三维几何形状被控制在纳米精度，具有两个不同的键，其亲和度被控制在kbt精度，通过静态光散射在原位量化。计算模型使用亚单位、短程电位和朗之万动力学的粗粒度表示。实验观察和建模表明，当键的亲和度不相等时，会发生两种不同的层次组装途径，其中亚基首先形成二聚体，而在另一种情况下形成五聚体。与所有结合位点具有同等强度的平均途径相比，这些分层途径更快地产生完整的衣壳，并且对亲和力变化的抵抗力更强。这一发现表明，分层组装可能是优化复杂目标结构自组装的一般工程原理。
Self-assembly of complex and functional materials remains a grand challenge in soft material science. Efficient assembly depends on a delicate balance between thermodynamic and kinetic effects, requiring fine-tuning affinities and concentrations of subunits. By contrast, we introduce an assembly paradigm that allows large error-tolerance in the subunit affinity and helps avoid kinetic traps. Our combined experimental and computational approach uses a model system of triangular subunits programmed to assemble intoT= 3 icosahedral capsids comprising 60 units. The experimental platform uses DNA origami to create monodisperse colloids whose three-dimensional geometry is controlled to nanometer precision, with two distinct bonds whose affinities are controlled tokBTprecision, quantified in situ by static light scattering. The computational model uses a coarse-grained representation of subunits, short-ranged potentials, and Langevin dynamics. Experimental observations and modeling reveal that when the bond affinities are unequal, two distincthierarchicalassembly pathways occur, in which the subunits first form dimers in one case and pentamers in another. These hierarchical pathways produce complete capsids faster and are more robust against affinity variation than egalitarian pathways, in which all binding sites have equal strengths. This finding suggests that hierarchical assembly may be a general engineering principle for optimizing self-assembly of complex target structures.