2'-''O''-methylation is a common

nucleoside Nucleosides are glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleoside consists simply of a nucleobase (also termed a nitrogenous base) and a five-carbon sugar (ribose or 2'-deoxyribose) whereas a nucleotide ...

modification of

RNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

, where a

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many ...

is added to the 2' hydroxyl of the

ribose Ribose is a simple sugar and carbohydrate with molecular formula C5H10O5 and the linear-form composition H−(C=O)−(CHOH)4−H. The naturally-occurring form, , is a component of the ribonucleotides from which RNA is built, and so this compo ...

moiety of a nucleoside, producing a

methoxy In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position a ...

group. 2'-''O''-methylated nucleosides are mostly found in

ribosomal RNA Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal ...

and

small nuclear RNA Small nuclear RNA (snRNA) is a class of small RNA molecules that are found within the splicing speckles and Cajal bodies of the cell nucleus in eukaryotic cells. The length of an average snRNA is approximately 150 nucleotides. They are transcribe ...

and occur in the functionally essential regions of the

ribosome Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to ...

and

spliceosome A spliceosome is a large ribonucleoprotein (RNP) complex found primarily within the nucleus of eukaryotic cells. The spliceosome is assembled from small nuclear RNAs (snRNA) and numerous proteins. Small nuclear RNA (snRNA) molecules bind to specifi ...

. Currently, about 1210 2'-''O''-methylations (2'-''O''-Me) have been identified in mammals and yeast and deposited in

RMBase (RNA Modification Base) RMBase (RNA Modification Base) is designed for decoding the landscape of RNA modifications identified from high-throughput sequencing data (MeRIP-seq, m6A-seq, miCLIP, m6A-CLIP, Pseudo-seq, Ψ-seq, CeU-seq, Aza-IP, RiboMeth-seq). It contains ~12 ...

database. Having chemical properties intermediate between RNA and DNA, 2'-''O''-methylation is presumed to have been one of the reactive group of RNA molecules on early earth that would have given rise to DNA. A novel method, Nm-REP-seq, was developed for enriching ribose methylations by using RNA exoribonuclease (Mycoplasma genitalium RNase R, MgR) and periodate oxidation reactivity to eliminate 2'-hydroxylated (2'-OH) nucleosides. Nm-REP-seq utilizes two orthogonal lines of evidences for the single-nucleotide detection of 2'-O-Methylation sites in various ncRNAs and mRNAs. Nm-REP-seq discovered telomerase RNA component (TERC) RNA, scaRNAs and snoRNAs as new classes of Nm-containing ncRNAs. Furthermore, Nm-REP-seq revealed 2'-O-Methylation located at the 3’-end of snoRNAs, snRNAs, tRNAs and fragments derived from them, as well as piRNAs and miRNAs. A method to map 2'-''O'' ribose methylations by high throughput sequencing has been published. The method maps modifications of rRNAs in a single experiment.

References

RNA O-methylation {{Molecular-biology-stub

See also

References