Rodriguez Antony, Griffiths-Jones Sam, Ashurst Jennifer L, Bradley Allan
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom.
Genome Res. 2004 Oct;14(10A):1902-10. doi: 10.1101/gr.2722704. Epub 2004 Sep 13.
To derive a global perspective on the transcription of microRNAs (miRNAs) in mammals, we annotated the genomic position and context of this class of noncoding RNAs (ncRNAs) in the human and mouse genomes. Of the 232 known mammalian miRNAs, we found that 161 overlap with 123 defined transcription units (TUs). We identified miRNAs within introns of 90 protein-coding genes with a broad spectrum of molecular functions, and in both introns and exons of 66 mRNA-like noncoding RNAs (mlncRNAs). In addition, novel families of miRNAs based on host gene identity were identified. The transcription patterns of all miRNA host genes were curated from a variety of sources illustrating spatial, temporal, and physiological regulation of miRNA expression. These findings strongly suggest that miRNAs are transcribed in parallel with their host transcripts, and that the two different transcription classes of miRNAs ('exonic' and 'intronic') identified here may require slightly different mechanisms of biogenesis.
为了从全局角度了解哺乳动物中微小RNA（miRNA）的转录情况，我们注释了人类和小鼠基因组中这类非编码RNA（ncRNA）的基因组位置和背景。在232个已知的哺乳动物miRNA中，我们发现有161个与123个已定义的转录单元（TU）重叠。我们在90个具有广泛分子功能的蛋白质编码基因的内含子中，以及66个mRNA样非编码RNA（mlncRNA）的内含子和外显子中鉴定出了miRNA。此外，还基于宿主基因身份鉴定出了新的miRNA家族。所有miRNA宿主基因的转录模式均来自各种来源，展示了miRNA表达的空间、时间和生理调控。这些发现有力地表明，miRNA与其宿主转录本平行转录，并且这里鉴定出的两种不同转录类型的miRNA（“外显子型”和“内含子型”）可能需要略有不同的生物合成机制。
