Commentary
Divergent lncRNAs take the lead on pluripotent cell differentiation
Abstract
A better understanding of the overall transcriptional landscape of human cells has been possible due to the ENCODE and FANTOM projects (1-3). It emerged that mammalian genomes are more intricate than previously suspected and produce a lattice of transcripts, among which only 2% encodes for proteins (4,5). Although alternative splicing and the presence of different Transcription Start Sites can concur to this complexity, a huge part of it can be explained by the existence of short (<30 nt) and long
(>200 nt) non-coding RNAs (ncRNAs) which exert their roles without being translated into proteins (6,7). These include the long non-coding RNAs (lncRNAs), which represent a large and diverse class of RNA polymerase II transcripts longer than 200 nucleotides and act as fine-tuners of gene expression by a range of mechanisms (8). LncRNAs have histone-modification profiles, splicing signals, and exon/intron lengths akin to protein-coding genes. However, despite these similarities, lncRNAs are low expressed, preponderant in the nucleus and highly tissue-specific suggesting potential roles in specifying cell identity (9-11) and, when deregulated, in disease (12-14).
(>200 nt) non-coding RNAs (ncRNAs) which exert their roles without being translated into proteins (6,7). These include the long non-coding RNAs (lncRNAs), which represent a large and diverse class of RNA polymerase II transcripts longer than 200 nucleotides and act as fine-tuners of gene expression by a range of mechanisms (8). LncRNAs have histone-modification profiles, splicing signals, and exon/intron lengths akin to protein-coding genes. However, despite these similarities, lncRNAs are low expressed, preponderant in the nucleus and highly tissue-specific suggesting potential roles in specifying cell identity (9-11) and, when deregulated, in disease (12-14).
