部分基因组可能是新蛋白质形成的关键

Researchers in Biomedical Informatics at IMIM (Hospital del Mar¹ Medical Research Institute) and at the Universitat Politècnica de Catalunya (UPC) have recently published a study in eLife showing that RNA called non-coding (IncRNA) plays an important role in the evolution of new proteins, some of which could have important cell functions yet to be discovered. Ribosomes produce proteins from the instructions found in an RNA molecule². However, only 2% of the human genome is RNA containing information for the synthesis of proteins, meaning it is coding. Other parts of the genome that are transcribed³ could be "evolutionary⁴ noise," parts of the DNA⁵ that are copied to RNA randomly⁶ but with no concrete biological function. Now, a new sequencing technique has revealed that many of these transcripts⁷ (IncRNAs) may also translate into proteins, leading to an intense debate.   "We have confirmed that in all six species that were studied -human beings, mice, fish, flies, yeast⁸ and a plant- many of the IncRNAs were associated to ribosomes and seemed to be ready to translate RNA into proteins. This suggests that they could act as a repository for the synthesis of new proteins" explains Mar Albà, a professor at ICREA and the coordinator⁹ for the research group on Evolutionary Genomics at IMIM.   The study has found almost 2,500 IncRNAs that had not been studied, besides those identified previously¹⁰, and has shown that very few IncRNAs are in more than one species. This would suggest that they have evolved recently. This hypothesis is backed by the fact that the properties of the IncRNA molecules¹¹ show many similarities with the properties of "young" genes¹² that are known to produce proteins.   "The birth of a new functional¹³ protein is a trial and error process that probably requires the production of many transcripts that will not survive the test of time, and IncRNA seems to fit this role. The study of closely related species will allow us to better understand how new coding genes are formed and identify those that can be functional. It will also be interesting to study the link between the alteration¹⁴ of IncRNA expression patterns and certain diseases" concludes Mar Albà.