tRNA-5-Methylaminomethyl-2-Thiouridylate Methyltransferase (TRMU)

TRMU is a member of the trmU family. It encodes a mitochondria-specific tRNA-modifying enzyme that is required for the 2-thio modification of 5-taurinomethyl-2-thiouridine tRNA-Lys on the wobble position of the anticodon.

The full-length 421-amino acid protein has a calculated molecular mass of 47.7 kD. The other transcripts lack exon 3 and encode a deduced 99-amino acid protein. Northern blot analysis detected high expression of a 1.9-kb TRMU transcript in heart, skeletal muscle, and kidney. Intermediate expression was detected in brain, placenta, spleen, and small intestine, and low expression was detected in liver, colon, lung, thymus, and leukocytes. Expression was nearly uniform in 8 brain regions examined.