Reaction: S-adenosyl-L-methionine + cytosine34 in tRNA precursor = S-adenosyl-L-homocysteine + 5-methylcytosine34 in tRNA precursor
Other name(s): hTrm4 Mtase; hTrm4 methyltransferase; hTrm4 (gene name); tRNA:m5C-methyltransferase (ambiguous)
Systematic name: S-adenosyl-L-methionine:tRNA (cytosine34-C5)-methyltransferase
Comments: The human enzyme is specific for C5-methylation of cytosine34 in tRNA precursors. The intron in the human pre-tRNALeu(CAA) is indispensable for the C5-methylation of cytosine in the first position of the anticodon. It is not able to form 5-methylcytosine at positions 48 and 49 of human and yeast tRNA precursors .
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. Brzezicha, B., Schmidt, M., Makalowska, I., Jarmolowski, A., Pienkowska, J. and Szweykowska-Kulinska, Z. Identification of human tRNA:m5C methyltransferase catalysing intron-dependent m5C formation in the first position of the anticodon of the pre-tRNA Leu (CAA). Nucleic Acids Res. 34 (2006) 6034-6043. [PMID: 17071714]