SYNTHESIS OF POLYRIBONUCLEOTIDES OF DEFINED SEQUENCE

总体计划是开发一种化学方法来合成 10-20 mg量的确定序列的寡核糖核苷酸， 这些分子，以评估各种热力学稳定性 RNA中的结构。 综合战略需要研究 核糖核苷的适当化学保护和 四种被保护的核糖核苷-3 ′芳基的钡盐的制备 磷酸二酯 这些单体对的缩合将产生 包含所有16种可能排列的二核苷酸“文库”。 的 单体和二聚体合成单元将用于构建 寡核糖核苷酸在溶液中和固相的发展 合成系统，将纳入一个机制，为恢复和 单位的回收利用。 将制备特殊的寡核苷酸组 用于评估能量参数（焓和熵的变化） 引起二级结构的形成，如螺旋，发夹， 环、凸起、不匹配和内部环。 最近邻 对这些参数的贡献将通过比较 母体分子的能量与衍生物质的能量， 它们要么通过特定的核苷酸插入，要么通过重排， 它们的序列的一部分。 预计这些能量值将 为RNA的预测提供了重要的定量基础。 从核苷酸序列的知识来分析二级结构。

The overall plan is to develop a chemical method for the synthesis of defined sequence oligoribonucleotides in 10-20 mg quantities and to sue these molecules to evaluate the thermodynamic stabilities of various structures that occur in RNA. The synthetic strategy will require a study of the appropriate chemical protection of ribonucleosides and the preparation of barium salts of the four protected ribonucleoside-3' aryl phosphodiesters. The condensation of pairs of these monomers will generate a dinucleotide "library" containing all 16 possible arrangements. The monomeric and dimeric synthetic units will be used in the construction of oligoribonucleotides in solution and in the development of a solid-phase synthetic system that will incorporate a mechanism for the recovery and recycling of the units. Special sets of oligonucleotides will be prepared for the evaluation of energy parameters (changes in enthalpy and entropy) arising out the formation of secondary structures such as helices, hair-pin loops, bulges, mismatches and interior loops. Nearest neighbor contributions to these parameters will be determined by comparing the energies of parent molecules with those of derivative species formed from them either by specific nucleotide insertions or by rearrangements of portions of their sequences. These energy values are expected to constitute a significant quantitative basis for the prediction of RNA secondary structure from the knowledge of nucleotide sequence.