Mitochondrially encoded tRNA leucine 2 (CUN) also known as MT-TL2 is a transfer RNA which in humans is encoded by the mitochondrialMT-TL2gene.[1]
Function
MT-TL2 is a small 71 nucleotide RNA (human mitochondrial map position 12266-12336) that transfers the amino acid leucine to a growing polypeptide chain at the ribosome site of protein synthesis during translation.
Structure
The MT-TL2 gene is located on the p arm of the mitochondrial DNA at position 12 and it spans 75 base pairs.[2] The structure of a tRNA molecule is a distinctive folded structure which contains three hairpin loops and resembles a three-leafed clover.[3]
Clinical significance
Mutations in MT-TL2 can result in multiple mitochondrial deficiencies and associated disorders, including cardiopathy, myopathy, and encephalomyopathy. A patient with a mutation G12315A was found with encephalomyopathy with ragged-red muscle fibers.[4] A patient with a mutation of A12320G exhibited mitochondrial myopathy, and showed signs of mitochondrial myopathy.[5] In addition, multiple individuals with a T12297C substitution showed signs of cardiomyopathy accompanied with varying degrees.[6]
^Ronchi D, Virgilio R, Bordoni A, Fassone E, Sciacco M, Ciscato P, Moggio M, Govoni A, Corti S, Bresolin N, Comi GP (May 2010). "The m.12316G>A mutation in the mitochondrial tRNA Leu(CUN) gene is associated with mitochondrial myopathy and respiratory impairment". Journal of the Neurological Sciences. 292 (1–2): 107–10. doi:10.1016/j.jns.2010.01.026. PMID20163808. S2CID10403077.