5-Methyluridine

{{Short description|One of the five major nucleosides in nucleic acids}}

{{Distinguish|uridine|thymidine|thymine}}

{{Chembox

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| verifiedrevid = 477225363

| ImageFile=5-Methyluridin.svg

| ImageSize=150px

| ImageAlt = Skeletal formula of 5-methyluridine

| ImageFile1 = Ribothymidine 3D spacefill.png

| ImageSize1 = 170

| ImageAlt1 = Space-filling model of the 5-methyluridine molecule

| IUPACName=5-Methyluridine

| SystematicName=1-[(2R,3R,4S,5R)-3,4-Dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-5-methylpyrimidine-2,4(1H,3H)-dione

| OtherNames=Ribothymidine, Ribosylthymine; Thymine riboside, m5U

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChemSpiderID = 393058

| SMILES = CC1=CN(C(=O)NC1=O)[C@H]2[C@@H]([C@@H]([C@H](O2)CO)O)O

| InChI = 1/C10H14N2O6/c1-4-2-12(10(17)11-8(4)16)9-7(15)6(14)5(3-13)18-9/h2,5-7,9,13-15H,3H2,1H3,(H,11,16,17)/t5-,6-,7-,9-/m1/s1

| InChIKey = DWRXFEITVBNRMK-JXOAFFINBW

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/C10H14N2O6/c1-4-2-12(10(17)11-8(4)16)9-7(15)6(14)5(3-13)18-9/h2,5-7,9,13-15H,3H2,1H3,(H,11,16,17)/t5-,6-,7-,9-/m1/s1

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = DWRXFEITVBNRMK-JXOAFFINSA-N

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo=1463-10-1

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = ZS1409014A

| PubChem=445408

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|Section2={{Chembox Properties

| Formula=C₁₀H₁₄N₂O₆

| MolarMass=258.23 g/mol

| Appearance=

| Density=1,6 g/cm³{{cite web |url=http://www.chemspider.com/Chemical-Structure.29788257.html?rid=646f071c-9da8-46a6-be4c-b7497c5c9f0c&page_num=0 |title=5-Methyluridine |website=ChemSpider |access-date=December 6, 2018}}

| MeltingPtC=184{{cite book | author=William M. Haynes | title=CRC Handbook of Chemistry and Physics | edition=97th | year=2016 | publisher=CRC Press | location=Boca Raton | isbn=978-1-4987-5429-3 | page=3{{hyphen}}400 | url=https://books.google.com/books?id=VVezDAAAQBAJ}}

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|Section3={{Chembox Hazards

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The chemical compound 5-methyluridine (symbol m⁵U or m5U), also called ribothymidine (rT){{r|g=footnote|r=The term ribothymidine is especially used to describe its unusual occurrence in RNA.{{cite book |title=Lehninger Principles of Biochemistry |publisher=W. H. Freeman and Company |year=2013 |isbn=9781429234146 |edition=6th |pages=282 |language=en}}}}, is a pyrimidine nucleoside. It is the ribonucleoside counterpart to the deoxyribonucleoside thymidine, which lacks a hydroxyl group at the 2' position. 5-Methyluridine contains a thymine base joined to a ribose pentose sugar.{{cite journal|title=Catalytic crosslinking-based methods for enzyme-specified profiling of RNAribonucleotide modifications|author=Shobbir Hussain|journal=Methods|volume=156|year=2019|pages=60–65 |

doi=10.1016/j.ymeth.2018.10.003|pmid=30308313 |s2cid=52961265 |url=https://researchportal.bath.ac.uk/en/publications/5a05dcf5-c4df-4344-bc70-7877c5ef08bf}} It is a white solid.

m5U is one of the most common modifications made to cellular RNA. It almost universally occurs in position 54 (part of the T arm) of eukaryotic and bacterial tRNA, serving to stabilize the molecule. The same "T-loop" motif occurs in many other forms of noncoding RNA such as tmRNA and rRNA. Loss of the tRNA modification does not usually produce a different, less fit, phenotype.{{cite journal |last1=Powell |first1=CA |last2=Minczuk |first2=M |title=TRMT2B is responsible for both tRNA and rRNA m(5)U-methylation in human mitochondria. |journal=RNA Biology |date=April 2020 |volume=17 |issue=4 |pages=451–462 |doi=10.1080/15476286.2020.1712544 |pmid=31948311|doi-access=free |pmc=7237155}}