|Image credit: “Dna” by renjith krishnan at FreeDigitalPhotos.net|
Molecular biologists are finding a universe of functional small proteins and RNAs that were considered junk or not even known to exist.To finish reading, click on "Small Molecules Play Key Roles in Cells".
We often hear that 98% of the human genome is “noncoding” for proteins. This may be a very misleading statistic. Actually, most of the genome is transcribed into RNAs, whether or not those result in the large proteins we know about. Hidden in those transcripts are small molecules known as micro-RNAs, and some longer ones known as “long non-coding RNAs” (lncRNAs) that are increasingly seen as vital in gene regulation. And now, scientists are beginning to uncover transcripts that are translated into protein fragments. Too small to be called proteins, these polypeptides also play vital roles in cell health. The genes that program these small molecules, once dismissed as “junk DNA,” are revealing more sophistication in the genome than previously thought.