Resumen de Understanding the transcriptional landscape of non-coding genome in mammals
Widespread transcription in mammals revealed unexpected discovery of non-coding elements like long noncoding RNAs (lncRNAs) and repetitive elements. First, lncRNAs were previously identified in limited number of tissues or cell lines in mouse and the discovery of lncRNAs is still pending in many other tissues in mouse. To address this, we discovered 2,803 high-confidence novel lncRNAs by mapping and de novo assembling billions of RNA-seq reads in eight tissues and a primary cell line in mouse. Further, we integrated this catalog of lncRNAs with chromatin state maps and found many regulatory lncRNAs (promoter-associated and enhancer-associated lncRNAs). Second, more than half of the human genome contains repetitive elements. However, it is not clear how they are expressed across all mammalian tissues. To address this, as a part of Genotype-Tissue Expression (GTEx) project, we profiled repetitive elements using 8,551 poly-A RNA-seq datasets from 53 tissues across 550 individuals and found various repeat families transcribed across multiple human tissues in a tissue-specific manner. In summary, we find that repeat expression is a hallmark of tissue identity in humans.
