7-methylguanosine

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Structural formula
Structural formula of 7-methylguanosine
General
Surname 7-methylguanosine
other names
  • m 7 G (short code)
  • 9-β- D -ribofuranosyl-7-methylguanine
  • 9 - [(2 R , 3 R , 4 S , 5 R ) -3,4-dihydroxy-5- (hydroxymethyl) oxolan-2-yl] -2-amino-7-methyl-1 H -purine-6- on
Molecular formula C 11 H 16 N 5 O 5 +
External identifiers / databases
CAS number 20244-86-4
PubChem 135445750
ChemSpider 4976272
Wikidata Q72286919
properties
Molar mass 298.28 g mol −1
Physical state

firmly

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

7-methylguanosine (m 7 G) is a rare nucleoside and occurs in tRNA , rRNA and mRNA . It consists of β- D- ribofuranose (sugar) and 7-methylguanine . It is a derivative of guanosine which is methylated in the 7-position . It plays u. a. a role in the 5 'cap structure of the mRNA.

A tRNA Phe from S. cerevisiae .
7-methylguanosine is here with m 7 G in.

Occurrence

In addition to being found in tRNA and rRNA , 7-methylguanosine occurs in the 5'-cap structure of eukaryotic mRNA .

When it leaves the transcription apparatus , the nascent pre-mRNA comes into contact with the cap bound to the RNA polymerase II (5'-cap structure). First , a γ-phosphate is split off from the 5 'end of the pre-mRNA, which contains a nucleotide . Of a molecule GTP is guanosine to release a diphosphate continued the pre-mRNA. This is done by a 5'-5 'linkage of the phosphate group of guanosine with the diphosphate 5' end of the pre-mRNA. This is followed by the methylation of guanosine in position 7 with consumption of SAM . The cap of the RNA is an important structure in eukaryotes, which protects mRNA from degradation by 5'-3 'RNAses and forms the prerequisite that the RNA is recognized by the cap-binding complex for export from the cell nucleus .

See also

Individual evidence

  1. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  2. ↑ Patrick A. Limbach, Pamela F. Crain, James A. McCloskey: "Summary: the modified nucleosides of RNA", Nucleic Acids Research , 1994 , 22  (12), pp. 2183-2196 ( doi : 10.1093 / nar / 22.12 .2183 , PMC 523672 (free full text), PMID 7518580 ).
  3. ↑ H. Shi, PB Moore : "The crystal structure of yeast phenylalanine tRNA at 1.93 Å resolution: a classic structure revisited", RNA , 2000 , 6  (8), pp. 1091-1105 ( PMC 1369984 (free full text); PMID 10943889 ).
  4. ↑ Daniel Boujard, Bruno Anselme, Christophe Cullin, Céline Raguénès-Nicol: cellular and molecular biology at a glance . Springer, Berlin / Heidelberg 2014, ISBN 978-3-642-41760-3 , pp. 106 , doi : 10.1007 / 978-3-642-41761-0 .

Web links

  • Entry for 7-Methylguanosine in the Human Metabolome Database (HMDB) , accessed September 25, 2013.
  • Modification Summary of 7-Methylguanosine in the Modomics database, accessed January 14, 2014.