#noncodingrna

The ability to sequence genomes and characterize their products has begun to reveal the central role for regulatory RNAs in biology, ... especially in complex organisms like humans! It is now evident that the human genome contains not only protein-coding genes, but also tens of thousands of non–protein coding genes that express small and long ncRNAs (non-coding RNAs). Rapid progress in characterizing these ncRNAs has identified a diverse range of subclasses that play a crucial roles in many cellular pathways, including the differentiation and development of cells and organs and, when mis-regulated, in a number of diseases, including cancer. A review essay published this month describes ncRNAs in relatively non-technical terms.

Noncoding RNAs (ncRNAs) are transcripts that have no apparent protein-coding capacity; however, many ncRNAs have been found to play a major biological role in human physiology. Their deregulation is implicated in many human diseases, but their exact roles are only beginning to be elucidated. The figure shows a graphical representation of the complexity of the transcriptional landscape in mammals. White boxes represent non-coding exonic sequences and dark blue boxes protein-coding exonic sequences. Green diamonds represent snoRNAs and orange triangles represent miRNAs. Indicated are (A) antisense transcripts with overlapping exons, (B) nested transcripts on both strands, (C) antisense transcripts with interlacing exons and (D) retained introns. Click the photo to go to the paper (free online) for a discussion of ncRNAs.