The combination of pervasive transcription and prolific alternative splicing produces a mammalian transcriptome of great breadth and diversity. The majority of transcribed genomic bases are intronic, antisense, or intergenic to protein-coding genes, yielding a plethora of short and long non-protein-coding regulatory RNAs. Long noncoding RNAs (lncRNAs) share most aspects of their biogenesis, processing, and regulation with mRNAs. However, lncRNAs are typically expressed in more restricted patterns, frequently from enhancers, and exhibit almost universal alternative splicing. These features are consistent with their role as modular epigenetic regulators. We describe here the key studies and technological advances that have shaped our understanding of the dimensions, dynamics, and biological relevance of the mammalian noncoding transcriptome.

中文翻译：

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哺乳动物非编码转录组的尺寸，动力学和相关性。

普遍的转录和多产的选择性剪接的结合产生了广谱和多样性的哺乳动物转录组。大多数转录的基因组碱基是蛋白质编码基因的内含子，反义序列或基因间碱基，产生大量的长短非蛋白质编码调控RNA。长非编码RNA（lncRNA）与mRNA共享其生物发生，加工和调控的大多数方面。但是，lncRNA通常以限制性更强的模式表达，通常由增强子表达，并且表现出几乎通用的可变剪接。这些特征与其作为模块化表观遗传调控子的作用是一致的。我们在这里描述了关键的研究和技术进步，这些形成了我们对哺乳动物非编码转录组的尺寸，动态和生物学相关性的理解。