Monnard Pierre-Alain, Szostak Jack W
Los Alamos National Laboratory, EES-6, PO Box 1663, MS-D462, Los Alamos, NM 87545, USA.
J Inorg Biochem. 2008 May-Jun;102(5-6):1104-11. doi: 10.1016/j.jinorgbio.2008.01.026. Epub 2008 Feb 1.
The emergence of an RNA world requires among other processes the non-enzymatic, template-directed replication of genetic polymers such as RNA or related nucleic acids, possibly catalyzed by metal-ions. The absence of uridilate derivative polymerization on adenine containing templates has been the main issue preventing an efficient template-directed RNA polymerization. We report here the investigation of template-directed RNA polymerization in the eutectic phase in water-ice. In particular, it was found that activated uridilate monomers in the presence of metal-ion catalysts could efficiently elongate RNA hairpins whose 5'-overhangs served as the templating sequence. The same applies for every other pyrimidine and purine nucleobase. Moreover, the initial elongation rates were always higher in the presence of a template complementary to the nucleotide than in systems without proper base-pairing opportunities. These results suggest that a template-directed RNA polymerization catalyzed by metal-ions could be carried out under eutectic phase in water-ice conditions.
RNA世界的出现除其他过程外，还需要遗传聚合物（如RNA或相关核酸）的非酶促、模板导向复制，这可能由金属离子催化。在含腺嘌呤的模板上缺乏尿苷酸衍生物聚合一直是阻碍高效模板导向RNA聚合的主要问题。我们在此报告了对水冰中共晶相模板导向RNA聚合的研究。特别地，发现金属离子催化剂存在下的活化尿苷酸单体可以有效地延长RNA发夹结构，其5'端突出端作为模板序列。其他嘧啶和嘌呤碱基也是如此。此外，在存在与核苷酸互补的模板的情况下，初始延伸速率总是高于没有适当碱基配对机会的系统。这些结果表明，金属离子催化的模板导向RNA聚合可以在水冰条件下的共晶相中进行。
