Ubiquitous antisense transcription in eukaryotes: novel regulatory mechanism or byproduct of opportunistic RNA polymerase?
Ubiquitous antisense transcription in eukaryotes: novel regulatory mechanism or byproduct of opportunistic RNA polymerase?
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DOI：
10.3410/b1-33
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发表时间：
2009-04-29
期刊：
影响因子：
--
通讯作者：
Weil PA
中科院分区：
文献类型：
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作者：
Layer JH;Weil PA
在过去的几年里，在基因调控方面有一个比较值得注意的观察，那就是真核生物的基因组似乎普遍被转录。最近的转录组图谱研究表明，大部分基因组是转录的，在某些情况下，来自特定基因组位点的两条链的转录本都是可检测的。虽然其中一些转录物映射到已知的RNA聚合酶II转录单位[即蛋白质编码开放阅读框（orf）]，但许多转录物来自被认为是非基因的DNA区域。模板结合RNA聚合酶II的平行染色质免疫沉淀研究表明，它确实驻留在那些被发现转录的区域，无论是ORF还是非ORF。然而，这些普遍转录本的链结性从未在全基因组的基础上被测量过。最近的四份报告解决了这个问题，并在此过程中惊人地发现，mRNA意义基因转录的许多位点与非常活跃的反义或发散转录相关，这种转录从转录起始位点开始，并向上游方向进行。
One of the more notable observations made in the last few years in gene regulation is that eukaryotic genomes appear to be pervasively transcribed. Recent transcriptome mapping studies have shown that much of the genome is transcribed, and in some instances transcripts from both strands of specific genomic loci are detectable. While some of these transcripts map to known RNA polymerase II transcription units [that is, protein encoding open reading frames (ORFs)], many are derived from regions of DNA thought to be non-genic. Parallel chromatin immunoprecipitation studies of template-bound RNA polymerase II have shown that it is indeed resident on those regions found to be transcribed, both ORF and non-ORF. However, the strandedness of these pervasive transcripts has never been measured on a genome-wide basis. Four recent reports have addressed this question and, in the process, have made the startling discovery that many loci of mRNA sense gene transcription are associated with very active antisense or divergent transcription that begins at mapped transcription start sites and proceeds in an upstream direction.