Non-coding RNA
A non-coding RNA (ncRNA) is a functional RNA molecule which is not translated into a protein. Less-used synonyms are non-protein-coding RNA (npcRNA), non-messenger RNA (nmRNA) and functional RNA (fRNA). The term small RNA (sRNA) is often used for short bacterial ncRNAs. The DNA sequence from which a non-coding RNA is transcribed is often called an 'RNA gene'.
Non-coding RNA genes include abundant and important RNAs such as transfer RNA (tRNA) and ribosomal RNA (rRNA); also RNAs such as snoRNAs, microRNAs, siRNAs, snRNAs, exRNAs, and piRNAs and the long noncoding RNAs (long ncRNAs). The number of ncRNAs in the human genome is unknown. However recent studies suggest the existence of thousands of ncRNAs.[1][2][3][4], but see [5] Since the function of newly identified ncRNAs has not been proved, it is possible that many are non-functional.[6]
The first non-coding RNA to be analysed was an alanine tRNA found in baker's yeast. Its structure was published in 1965.[7]
Non-coding RNA Media
The roles of non-coding RNAs: Ribonucleoproteins are shown in red, non-coding RNAs in blue.
The cloverleaf structure of Yeast tRNAPhe (inset) and the 3D structure determined by X-ray analysis.
Atomic structure of the 50S Subunit from Haloarcula marismortui. Proteins are shown in blue and the two RNA strands in orange and yellow. The small patch of green in the center of the subunit is the active site.
Electron microscopy images of the yeast spliceosome. Note the bulk of the complex is in fact ncRNA.
References
- ↑ Cheng J. Transcriptional maps of 10 human chromosomes at 5-nucleotide resolution.. Science 308 (5725) (2005). p. 1149–54. doi:10.1126/science.1108625.
- ↑ ENCODE Project Consortium. Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project. Nature 447 (7146) (2007). p. 799–816. doi:10.1038/nature05874.
- ↑ Washietl S. Structured RNAs in the ENCODE selected regions of the human genome. Genome Res 17 (6) (2007). p. 852–64. doi:10.1101/gr.5650707.
- ↑ Morris K.V. (ed) 2012. Non-coding RNAs and epigenetic regulation of gene expression: drivers of natural selection. Non-coding RNAs and Epigenetic Regulation of Gene Expression: Drivers of Natural Selection (2012)Caister Academic Press. ISBN 978-1-904455-94-3.
- ↑ van Bakel H. Most "dark matter" transcripts are associated with known genes. PLOS Biol 8 (5) (2010). p. e1000371. doi:10.1371/journal.pbio.1000371.
- ↑ Hüttenhofer A; Schattner P. & Polacek N. Non-coding RNAs: hope or hype?. Trends Genet 21 (5) (2005). p. 289–97. doi:10.1016/j.tig.2005.03.007.
- ↑ Holley R.W.. Structure of a riboucleic acid. Science 147 (3664) (1965). p. 1462–5. doi:10.1126/science.147.3664.1462. Retrieved 2010-09-03.