TRNA methyltransferase

Function

tRNA methyltransferase (Trm) methylates specific positions on tRNA. tRNA methylation is a post-transcription modification. The methyl donor is S-adenosylmethionine (SAM) and the product is the methylated tRNA and S-adenosylhomocysteine (SAH)^[1]. S-adenosylornithine or sinefugin (SFG) is an inhibitor of the reaction.

For details on Trm to N2 of guanine 6 see TRNA:m2G6 methyltransferase TrmN/Trm14.

• Dual specificity tRNA methyltransferase Rlmn is an E. coli methyltransferase which modifies both ribosomal 23S RNA and tRNA^[2].
• METTL6 modifies cytidine 32^[3].

Structural highlights

Trm is located at the cleft at the subunit interface^[4]. Water molecules are shown as red spheres.

3D structures of tRNA methyltransferase

tRNA methyltransferase 3D structures

References

1. ↑ Swinehart WE, Jackman JE. Diversity in mechanism and function of tRNA methyltransferases. RNA Biol. 2015;12(4):398-411. doi: 10.1080/15476286.2015.1008358. PMID:25626150 doi:http://dx.doi.org/10.1080/15476286.2015.1008358
2. ↑ Benitez-Paez A, Villarroya M, Armengod ME. The Escherichia coli RlmN methyltransferase is a dual-specificity enzyme that modifies both rRNA and tRNA and controls translational accuracy. RNA. 2012 Oct;18(10):1783-95. doi: 10.1261/rna.033266.112. Epub 2012 Aug 13. PMID:22891362 doi:http://dx.doi.org/10.1261/rna.033266.112
3. ↑ Ignatova VV, Kaiser S, Ho JSY, Bing X, Stolz P, Tan YX, Lee CL, Gay FPH, Lastres PR, Gerlini R, Rathkolb B, Aguilar-Pimentel A, Sanz-Moreno A, Klein-Rodewald T, Calzada-Wack J, Ibragimov E, Valenta M, Lukauskas S, Pavesi A, Marschall S, Leuchtenberger S, Fuchs H, Gailus-Durner V, de Angelis MH, Bultmann S, Rando OJ, Guccione E, Kellner SM, Schneider R. METTL6 is a tRNA m(3)C methyltransferase that regulates pluripotency and tumor cell growth. Sci Adv. 2020 Aug 26;6(35):eaaz4551. PMID:32923617 doi:10.1126/sciadv.aaz4551
4. ↑ Ahn HJ, Kim HW, Yoon HJ, Lee BI, Suh SW, Yang JK. Crystal structure of tRNA(m1G37)methyltransferase: insights into tRNA recognition. EMBO J. 2003 Jun 2;22(11):2593-603. PMID:12773376 doi:10.1093/emboj/cdg269