Voloshin O N, Veselkov A G, Belotserkovskii B P, Danilevskaya O N, Pavlova M N, Dobrynin V N, Frank-Kamenetskii M D
Institute of Molecular Genetics, M.M.Shemyakin Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow.
J Biomol Struct Dyn. 1992 Feb;9(4):643-52. doi: 10.1080/07391102.1992.10507945.
We have found, with the aid of 2-D gel electrophoresis, that double-stranded human telomeric repeat, (T2AG3)12.(C3TA2)12, being cloned within a plasmid, forms a protonated superhelically-induced structure. Experiments on chemical and enzymatic probing also indicate that the human telomeric repeats adopt an unusual structure. We have proposed an eclectic model for this structure in which four different elements coexist: a non-orthodox intramolecular triplex stabilized by the canonical protonated C.G*C+ base-triads and highly enriched by noncanonical base-triads; the intramolecular quadruplex formed by a portion of the G-rich strand; the single-stranded region encompassing a portion of the G-rich strand and, probably, the (C,A)-hairpin formed by a portion of the C-rich strand.
我们借助二维凝胶电泳发现，克隆于质粒中的双链人类端粒重复序列（T2AG3）12·（C3TA2）12形成了一种质子化的超螺旋诱导结构。化学和酶促探测实验也表明，人类端粒重复序列呈现出一种异常结构。我们针对这种结构提出了一个综合模型，其中四种不同的元件共存：一种由典型的质子化C.G*C+碱基三联体稳定且富含非典型碱基三联体的非正统分子内三链体；由富含G链的一部分形成的分子内四链体；包含富含G链一部分的单链区域，以及可能由富含C链的一部分形成的（C，A）发夹结构。
