Andersen Kasper R, Jensen Torben Heick, Brodersen Ditlev E
Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
Biochim Biophys Acta. 2008 Sep;1779(9):532-7. doi: 10.1016/j.bbagrm.2008.06.011. Epub 2008 Jul 8.
The overall fidelity of RNA biosynthesis and processing is very high. This goes for both mRNAs, which are turned over relatively quickly, and for stable RNAs, such as the components of the translational apparatus, the transfer and ribosomal RNAs. However, no enzymatic process is completely error-free, so to minimize the number of non-functional transcripts, the cell has degradation pathways in place to efficiently deal with those mistakes that inevitably occur. Though several "RNA surveillance" or "RNA quality control" systems have been described that are able to specifically eliminate misfolded and non-functional RNAs, we still do not understand neither what precise features define a faulty RNA, nor the molecular basis for recognition of such molecules. Nonetheless, our knowledge about the controlled degradation of both stable and labile RNAs is now converging into a unified picture that points to the poly(A) tail as a key discriminator of RNA quality in both bacteria and eukaryotes.
RNA生物合成与加工的整体保真度非常高。对于相对快速周转的信使RNA（mRNA）以及稳定的RNA（如翻译装置的组成成分、转运RNA和核糖体RNA）来说都是如此。然而，没有任何酶促过程是完全无差错的，因此为了尽量减少无功能转录本的数量，细胞具备降解途径，以有效处理不可避免出现的错误。尽管已经描述了几种能够特异性消除错误折叠和无功能RNA的“RNA监测”或“RNA质量控制”系统，但我们仍然既不了解定义有缺陷RNA的确切特征是什么，也不了解识别此类分子的分子基础。尽管如此，我们目前关于稳定和不稳定RNA受控降解的知识正在汇聚成一幅统一的图景，该图景表明聚腺苷酸（poly(A)）尾是细菌和真核生物中RNA质量的关键判别因素。
