Anant Shrikant, Davidson Nicholas O
Department of Internal Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.
Trends Mol Med. 2003 Apr;9(4):147-52. doi: 10.1016/s1471-4914(03)00032-7.
Post-transcriptional RNA editing generates novel gene products by changing the coding sequence of the transcript from that in the genome. Two classes of RNA editing exist in mammals, each of which involves an enzymatic deamination. These reactions have stringent sequence and structural requirements for their target RNAs, and each requires distinctive enzymatic machinery. Alterations in the expression or abundance of RNA-editing factors produce unanticipated alterations in the processing or expression of RNAs, in some cases outside their physiological targets. Recent findings suggest that unregulated expression of the cytidine-deaminase gene family might lead to deamination of deoxycytidine nucleotides in DNA. Aberrant or dysregulated RNA editing, or altered expression of editing factors, might contribute to genomic instability in cancer.
转录后RNA编辑通过改变转录本的编码序列（与基因组中的编码序列不同）来产生新的基因产物。哺乳动物中存在两类RNA编辑，每一类都涉及酶促脱氨反应。这些反应对其靶RNA有严格的序列和结构要求，并且每一类都需要独特的酶机制。RNA编辑因子表达或丰度的改变会在RNA的加工或表达中产生意想不到的改变，在某些情况下这些改变发生在其生理靶标之外。最近的研究结果表明，胞苷脱氨酶基因家族的不受调控表达可能导致DNA中脱氧胞苷核苷酸的脱氨。异常或失调的RNA编辑，或编辑因子表达的改变，可能导致癌症中的基因组不稳定。
