创造一种具有所期望的微观分子结构的宏观物体（如一种晶体）是一种挑战。一个比较有希望的方法是，使用具有坚固三维模体和粘性端部的大分子，这样将它们彼此搭接起来时，它们就会形成一个周期性排列，通过晶体学技术可对这种排列进行研究。
Zhang等人将DNA用于这一目的，DNA分子排列成一个被称为“tensegrity triangle”的结构模体，可生长成200微米大小的晶体，在其中原子的位置可以4埃的分辨率被确定。互补DNA链之间高度针对性的相互作用，使得晶体的单元格有可能实现所期望的、所设计的结构。后者还还具有周期性的洞，这些洞有可能被用来在一个三维周期排列中容纳生物分子，从而使得即使在它们自己不能结晶时也有可能确定它们的结构。（生物谷Bioon.com）
生物谷推荐原始出处：
Nature 461, 74-77 (3 September 2009) | doi:10.1038/nature08274
From molecular to macroscopic via the rational design of a self-assembled 3D DNA crystal
Jianping Zheng1,4, Jens J. Birktoft1,4, Yi Chen2,4, Tong Wang1, Ruojie Sha1, Pamela E. Constantinou1,5, Stephan L. Ginell3, Chengde Mao2 & Nadrian C. Seeman1
1 Department of Chemistry, New York University, New York 10003, USA
2 Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
3 Structural Biology Center, Argonne National Laboratory, Argonne, Illinois 60439, USA
4 These authors contributed equally to this work.
5 Present address: Department of Bioengineering, Rice University, 6100 Main Street, MS-142, Houston, Texas 77005, USA.
We live in a macroscopic three-dimensional (3D) world, but our best description of the structure of matter is at the atomic and molecular scale. Understanding the relationship between the two scales requires a bridge from the molecular world to the macroscopic world. Connecting these two domains with atomic precision is a central goal of the natural sciences, but it requires high spatial control of the 3D structure of matter1. The simplest practical route to producing precisely designed 3D macroscopic objects is to form a crystalline arrangement by self-assembly, because such a periodic array has only conceptually simple requirements: a motif that has a robust 3D structure, dominant affinity interactions between parts of the motif when it self-associates, and predictable structures for these affinity interactions. Fulfilling these three criteria to produce a 3D periodic system is not easy, but should readily be achieved with well-structured branched DNA motifs tailed by sticky ends2. Complementary sticky ends associate with each other preferentially and assume the well-known B-DNA structure when they do so3; the helically repeating nature of DNA facilitates the construction of a periodic array. It is essential that the directions of propagation associated with the sticky ends do not share the same plane, but extend to form a 3D arrangement of matter. Here we report the crystal structure at 4 ? resolution of a designed, self-assembled, 3D crystal based on the DNA tensegrity triangle4. The data demonstrate clearly that it is possible to design and self-assemble a well-ordered macromolecular 3D crystalline lattice with precise control.
