Broitman S L, Im D D, Fresco J R
Proc Natl Acad Sci U S A. 1987 Aug;84(15):5120-4. doi: 10.1073/pnas.84.15.5120.
A polynucleotide helical structure containing two strands of poly(A) and one of poly(U) is reported. As shown by spectroscopic observations, the complex only forms when the poly(A) strands are of Mr between 9000 and 50,000 (degree of polymerization congruent to 28-150), whereas the size of the poly(U) strand has no effect. This limitation may explain why poly(A.A.U) was not seen in previous investigations. The potential of the poly(A) tails of mRNA for formation of this triple helix and of A.A.U or/and A.A.T triplet formation to contribute to the binding of specific RNA strands to gene-encoding nucleic acid double helices are noted.
据报道，存在一种包含两条聚（A）链和一条聚（U）链的多核苷酸螺旋结构。光谱观察表明，只有当聚（A）链的分子量在9000至50,000之间（聚合度相当于28 - 150）时，该复合物才会形成，而聚（U）链的大小则没有影响。这一限制可能解释了为何在先前的研究中未观察到聚（A.A.U）。文中指出了mRNA的聚（A）尾形成这种三螺旋的可能性，以及A.A.U或/和A.A.T三联体形成对特定RNA链与基因编码核酸双螺旋结合的作用。
