Marsh T C, Vesenka J, Henderson E
Department of Zoology and Genetics, Iowa State University, Ames 50011.
Nucleic Acids Res. 1995 Feb 25;23(4):696-700. doi: 10.1093/nar/23.4.696.
G-DNA is a polymorphic family of quadruple helical nucleic acid structures containing guanine tetrad motifs [G-quartets; Williamson, J.R., Raghuraman, M.K. and Cech, T.R. (1989) Cell 59, 871-880; Williamson, J.R. (1993) Proc. Natl. Acad. Sci. USA 90, 3124-3124]. Guanine rich oligonucleotides that are self-complimentary, as found in many telomeric G-strand repeat sequences, form G-DNA in the presence of monovalent and/or divalent metal cations. In this report we use the atomic force microscope (AFM) to explore the structural characteristics of long, linear polymers formed by the telomeric oligonucleotide d(GGGGTTGGGG) in the presence of specific metal cations. In the AFM these polymers, termed G-wires, appear as filaments whose height and length are determined by the metal ions present during the self-assembly process. The highly ordered, controllable self-assembly of G-wires could provide a basis for developing advanced biomaterials.
G-DNA是一个包含鸟嘌呤四联基序（G-四联体；威廉姆森，J.R.，拉古勒曼，M.K.和切赫，T.R.（1989年）《细胞》59卷，871 - 880页；威廉姆森，J.R.（1993年）《美国国家科学院院刊》90卷，3124 - 3124页）的四链螺旋核酸结构的多态家族。在许多端粒G链重复序列中发现的富含鸟嘌呤的自互补寡核苷酸，在一价和/或二价金属阳离子存在的情况下形成G-DNA。在本报告中，我们使用原子力显微镜（AFM）来探索在特定金属阳离子存在下由端粒寡核苷酸d(GGGGTTGGGG)形成的长线性聚合物的结构特征。在AFM中，这些聚合物，称为G线，表现为细丝，其高度和长度由自组装过程中存在的金属离子决定。G线的高度有序、可控的自组装可为开发先进生物材料提供基础。
