New class of gene-termini-associated human RNAs suggests a novel RNA copying mechanism

作者：Kapranov Philipp^*; Ozsolak Fatih; Kim Sang Woo; Foissac Sylvain; Lipson Doron; Hart Chris; Roels Steve; Borel Christelle; Antonarakis Stylianos E; Monaghan A Paula; John Bino; Milos Patrice M

来源：Nature, 2010, 466(7306): 642-646.

DOI：10.1038/nature09190

Small (<200 nucleotide) RNA (sRNA) profiling of human cells using various technologies demonstrates unexpected complexity of sRNAs with hundreds of thousands of sRNA species present(1-4). Genetic and in vitro studies show that these RNAs are not merely degradation products of longer transcripts but could indeed have a 1,2,5). Furthermore, profiling of RNAs, including the sRNAs, can reveal not only novel transcripts, but also make clear predictions about the existence and properties of novel biochemical pathways operating in a cell. For example, sRNA profiling in human cells indicated the existence of an unknown capping mechanism operating on cleaved RNA(2), a biochemical component of which was later identified(6). Here we show that human cells contain a novel type of sRNA that has non-genomically encoded 5' poly(U) tails. The presence of these RNAs at the termini of genes, specifically at the very 3' ends of known mRNAs, strongly argues for the presence of a yet uncharacterized endogenous biochemical pathway in cells that can copy RNA. We show that this pathway can operate on multiple genes, with specific enrichment towards transcript-encoding components of the translational machinery. Finally, we show that genes are also flanked by sense, 3' polyadenylated sRNAs that are likely to be capped.

• 出版日期2010-7-29