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Methyl-7-guanosine

The 1-methoxy-compound " is not formed, but rather 7-methyl guanosine (32b), with a betaine structured - "... [Pg.266]

Weber, L. A., Hickey, E.D., Nuss, D.L. Bayloni, C. (1977). 5 -terminal 7-methyl-guanosine and messenger RNA function influence of potassium concentration on translation in vitro. Journal of Biological Chemistry, 252, 4007-10. [Pg.114]

Another triphosphate synthesis is described in reference [94], where a partially protected hexaribonucleotide derivative is converted by CDI into the imidazolide and subsequently condensed with a protected 7-methyl guanosine diphosphate to give the triphosphate. [Pg.260]

Particularily interesting is the reaction of V with guanine and guanosine. The latter gives exclusively the 7-methyl guanosine. Guanine results in methylation at several sites. [Pg.83]

In a further experiment we assayed for the presence of a cap structure on the mRNAs for both Inhibitors I and II by competitive inhibition by 7-methyl-guanosine 5 -monophosphate (m G p) of the in vitro translation of these messengers. Concentrations of 40 pM m G p inhibited by 50% the in vitro translation of total tomato leaf poly(A)" " mRNA (Fig. 7A). This level is 40-fold lower than that required to similarly inhibit rabbit globin mRNA translated in a rabbit reticulocyte lysate (17) and 4-fold lower than that required to inhibit the same mRNA in a wheat germ system (18). It was of interest that the translation of Inhibitor I is inhibited to 50% by 20 pM m G p while 50% inhibition of Inhibitor II requires less than 10 pM (Fig. 7B). The basis of this difference is not understood but... [Pg.116]

Addition of a 3 poly-A tail and a 5 -7-methyl guanosine cap to mRNA. [Pg.427]

Prokaryotic mRNA is generally identical to its primary transcript, whereas eukaryotic mRNA is extensively modified posttranscriptionally. For example, a 7-methyl-guanosine "cap" is attached to the 5-terminal end of the mRNA through a triphosphate linkage by guanylyl-transferase. A long poly-Atail—not transcribed from the DNA—is attached to the 3 -end of most mRNAs. Many eukaryotic mRNAs also contain introns that must be removed to make the mRNA functional. Their removal requires small nuclear RNAs. [Pg.505]

Figure 23-7 Structure of 7-methyl-guanosine capped eukaryotic mRNA. (From Stryer, L. (1988) Biochemistry,... Figure 23-7 Structure of 7-methyl-guanosine capped eukaryotic mRNA. (From Stryer, L. (1988) Biochemistry,...
In vitro, the fidelity of translation is strongly influenced by the concentration of Mg2 + ions in the reaction. In the range from 1 to 4 mM Mg2 +, the ribosome will require a Shine-Delgarno sequence (prokaryotic) or a 7-methyl-guanosine cap (eukaryotic) on the mRNA before translation will initiate. For this reason, in vitro translation experiments performed with naturally occurring mRNAs are most... [Pg.375]

Substituted purines may arise in mixtures with 9-substituted derivatives from direct alkylation of purine anions. They are best prepared however by Traube syntheses. Thus formylation of 4,5-diamino-6-benzylthiopyrimidine and ethylation of the formyl derivatives gave a formamidopyrimidine which readily cyclized to 6-benzylthio-7-ethylpurine in the presence of potassium carbonate (B-68MI40901, p. 31). The derivative is clearly a ready source of 7-substituted adenines by reaction with ammonia or amines, or of 7-substituted purines by dethiation with Raney nickel. 7-Methylguanine has also been obtained from 7-methyl-guanosine, sodium borohydride and aniline at pH 4.5 (B-78MI40903, p. 615). [Pg.595]

Overview of RNA processing showing 7-methyl guanosine cap addition to the 50 end, processing of hnRNA into mRNA by the process of RNA splicing,... [Pg.693]

Eukaryotic mRNAs contain an unusual 7-methyl guanosine at the 50 end of the transcript called a 50 cap. This guanosine is added to the transcript shortly after RNA synthesis is initiated by enzymes associated with the RNA pol II elongation complex. There is an unusual 50,50-triphosphate linkage in the 50 cap between the guanosine and the first nucleotide of the mRNA (usually adenine), as shown in Figure 25.9. [Pg.709]

In the first modification, a cap structure is enzymatically added to the 5 end of the primary transcript. The cap structure (Figure 24.14) consists of 7-methyl-guanosine attached to the 5 end of the RNA by a 5 -5 triphosphate bridge. The first two nucleotides of the mRNA are also methylated. The cap structure is required for efficient translation of the final mature mRNA. [Pg.728]

Haller, A. A., Sarnow, P. (1997). In vitro selection of a 7-methyl-guanosine binding RNA that inhibits translation of capped mRNA molecules. Proc Natl Acad Sci U S A 94, 8521-8526. [Pg.56]

Enzymic methods of nucleoside i thesis continue to attract attention, and the sjmthesis of radiolabelled ribo- and deoxyribonucleosides by transglycosylation catalysed by crude E.coU homogenates has been reviewed.27 A promising method for the enzymic synthesis of nucleosides is illustrated by the example of virazole synthesis in Scheme 1 the use of A/7-methyl guanosine... [Pg.207]


See other pages where Methyl-7-guanosine is mentioned: [Pg.304]    [Pg.583]    [Pg.423]    [Pg.1641]    [Pg.720]    [Pg.304]    [Pg.36]    [Pg.234]    [Pg.374]    [Pg.374]    [Pg.534]    [Pg.278]    [Pg.1396]    [Pg.323]    [Pg.724]    [Pg.730]    [Pg.728]    [Pg.424]    [Pg.767]    [Pg.707]    [Pg.43]    [Pg.153]    [Pg.131]    [Pg.424]    [Pg.73]    [Pg.537]    [Pg.31]    [Pg.66]    [Pg.103]    [Pg.189]   
See also in sourсe #XX -- [ Pg.53 , Pg.55 ]

See also in sourсe #XX -- [ Pg.53 , Pg.55 ]




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Guanosin

Guanosine

Guanosine 5-phosphate, methylation

Guanosines, methylation

Guanosines, methylation

Methylated guanosine

Methylated guanosine

Trimethylenediamine-bis[guanosine 5 -(methyl

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