Wednesday, 26th February, 2014, 11:00

Are long non-coding RNAs translated?: Ribosome profiling reveals the complexity of eukaryotic proteomes

We have compiled raw sequencing data from ribosome profiling experiments performed in different species (human, mouse, zebrafish, fruit fly, yeast) and used them to assemble transcripts, quantify transcript-ribosome associations, and investigate the coding potential and strength of purifying selection of the putatively translated open reading frames in some long non-coding RNAs. We detected extensive association of lincRNAs with ribosomes, not only observed in mammals but also in the other eukaryotic groups. Surprisingly, some of the lncRNAs show significant sequence similarity to proteins only annotated in Genbank, whereas others show not such similarity but still contain putative short open reading frames. The coding potential of ribosome-associated lncRNAs ORFs, measured using different codon frequency based sequence statistics, is intermediate between intronic ORFs and experimentally validated ORFs. These ORFs are subject to weaker selective constraints than most experimentally validated proteins as inferred from single nucleotide polymorphism densities. Our results suggest that many lncRNAs have coding properties and that this class of genes most likely includes protein-coding genes that are no longer functional as well as genes encoding new, poorly-conserved, peptides.

Speaker: Jorge Ruiz Orera - Evolutionary Genomics, GRIB (IMIM - UPF)

Room Aula-4th floor