Department of Life Science, Graduate School of Advanced Engineering, Chiba Institute of Technology, Tsudanuma, 2-17-1, Narashino-shi, Chiba, 275-0016, Japan.
Department of Life and Environmental Sciences, Graduate School of Engineering, Chiba Institute of Technology, Tsudanuma, 2-17-1, Narashino-shi, Chiba, 275-0016, Japan.
Sci Rep. 2021 May 25;11(1):10920. doi: 10.1038/s41598-021-90427-9.
The 5'-UTR of HIV-1 genomic RNA is known to form specific structures and has important functions. There are three 5'-terminal sequences, G1, G2 and G3, with different localizations in the cell and virion particles as well as different efficiencies in translation and reverse transcription reactions. In the present study, the structural characteristics of the joint region between the TAR and PolyA stems was analysed, and it was found that small differences in the 5'-terminus affect the conformational characteristics of the stem-loop structures. In the G1 form, the two stems form a coaxial stem, whereas in the G2 and G3 forms, the two stems are structurally independent of each other. In the case of the G1 form, the 3'-flanking nucleotides of the PolyA stem are included in the stable coaxial stem structure, which may affect the rest of the 5'-UTR structure. This result demonstrates that the local conformation of this functionally key region has an important role in the function of the 5'-UTR.
HIV-1 基因组 RNA 的 5'-UTR 已知能形成特定的结构，并具有重要的功能。有三个 5'-末端序列，G1、G2 和 G3，它们在细胞和病毒粒子中的定位不同，在翻译和逆转录反应中的效率也不同。在本研究中，分析了 TAR 和 PolyA 茎之间的连接区的结构特征，发现 5'-末端的微小差异会影响茎环结构的构象特征。在 G1 形式中，两个茎形成同轴茎，而在 G2 和 G3 形式中，两个茎在结构上是相互独立的。在 G1 形式中，PolyA 茎的 3'-侧翼核苷酸包含在稳定的同轴茎结构中，这可能会影响 5'-UTR 结构的其余部分。这一结果表明，该功能关键区域的局部构象在 5'-UTR 的功能中起着重要作用。
