tRNA Methyltransferase 5 Homolog (TRMT5)

tRNAs contain as many as 13 or 14 nucleotides that are modified posttranscriptionally by enzymes that are highly specific for particular nucleotides in the tRNA structure. TRMT5 methylates the N1 position of guanosine-37 (G37) in selected tRNAs using S-adenosyl methionine. The deduced protein contains 500 amino acids. RT-PCR ELISA detected moderate to high expression of TRMT5 in all adult and fetal tissues examined, with highest expression in ovary, followed by testis, spinal cord, and liver. Moderate to high expression of TRMT5 was present in all specific brain regions examined, with highest expression in corpus callosum.Human TRM5 also methylated inosine at position 37, unlike TrmD. TRM5 did not have an absolute requirement for magnesium ions and appeared to function as a monomer.