TheMT-TL1 gene is located on thep arm of themitochondrial DNA at position 12 and it spans 75 base pairs.[2] The structure of atRNA molecule is a distinctive folded structure which contains three hairpin loops and resembles a three-leafedclover.[3]
MT-TL1 is a small 75 nucleotideRNA (human mitochondrial map position 3230–3304) that transfers the amino acidleucine to a growingpolypeptide chain at theribosome site ofprotein synthesis duringtranslation. Also, some studies showed that theMT-TL1 gene pathogenic variants could be attributed to the alterations of mTERF binding efficiency.[4]
MT-TP mutations may result in complex I deficiency of themitochondrial respiratory chain, which may cause a wide variety of signs and symptoms affecting many organs and systems of the body, particularly thenervous system, theheart, and the muscles used for movement (skeletal muscles). These signs and symptoms can appear at any time from birth to adulthood. Phenotypes of the condition includeencephalopathy,epilepsy,dystonia,hypotonia,myalgia,exercise intolerance, and more. A 3302A>G mutation has been found in a patient with the deficiency.[11]
^Anderson S, Bankier AT, Barrell BG, de Bruijn MH, Coulson AR, Drouin J, Eperon IC, Nierlich DP, Roe BA, Sanger F, Schreier PH, Smith AJ, Staden R, Young IG (April 1981). "Sequence and organization of the human mitochondrial genome".Nature.290 (5806):457–65.Bibcode:1981Natur.290..457A.doi:10.1038/290457a0.PMID7219534.S2CID4355527.
^Kameoka K, Isotani H, Tanaka K, Azukari K, Fujimura Y, Shiota Y, Sasaki E, Majima M, Furukawa K, Haginomori S, Kitaoka H, Ohsawa N (April 1998). "Novel mitochondrial DNA mutation in tRNA(Lys) (8296A→G) associated with diabetes".Biochemical and Biophysical Research Communications.245 (2):523–7.doi:10.1006/bbrc.1998.8437.PMID9571188.
^van den Bosch BJ, de Coo IF, Hendrickx AT, Busch HF, de Jong G, Scholte HR, Smeets HJ (October 2004). "Increased risk for cardiorespiratory failure associated with the A3302G mutation in the mitochondrial DNA encoded tRNALeu(UUR) gene".Neuromuscular Disorders.14 (10):683–8.doi:10.1016/j.nmd.2004.06.004.PMID15351426.S2CID38721676.
Ogle RF, Christodoulou J, Fagan E, Blok RB, Kirby DM, Seller KL, Dahl HH, Thorburn DR (January 1997). "Mitochondrial myopathy with tRNA(Leu(UUR)) mutation and complex I deficiency responsive to riboflavin".The Journal of Pediatrics.130 (1):138–45.doi:10.1016/S0022-3476(97)70323-8.PMID9003864.
Houshmand M, Larsson NG, Oldfors A, Tulinius M, Holme E (March 1996). "Fatal mitochondrial myopathy, lactic acidosis, and complex I deficiency associated with a heteroplasmic A → G mutation at position 3251 in the mitochondrial tRNALeu(UUR) gne".Human Genetics.97 (3):269–73.doi:10.1007/BF02185750.PMID8786060.S2CID6688307.
Suzuki Y, Nishimaki K, Taniyama M, Muramatsu T, Atsumi Y, Matsuoka K, Ohta S (March 2004). "Lipoma and opthalmoplegia in mitochondrial diabetes associated with small heteroplasmy level of 3243 tRNA(Leu(UUR)) mutation".Diabetes Research and Clinical Practice.63 (3):225–9.doi:10.1016/j.diabres.2003.10.024.PMID14757294.
Iwanaga R, Koga Y, Aramaki S, Kato S, Kato H (February 2001). "Inter- and/or intra-organ distribution of mitochondrial C3303T or A3243G mutation in mitochondrial cytopathy".Acta Neuropathologica.101 (2):179–84.doi:10.1007/s004010000266.PMID11271374.S2CID1970758.
Nishigaki Y, Tadesse S, Bonilla E, Shungu D, Hersh S, Keats BJ, Berlin CI, Goldberg MF, Vockley J, DiMauro S, Hirano M (May 2003). "A novel mitochondrial tRNA(Leu(UUR)) mutation in a patient with features of MERRF and Kearns-Sayre syndrome".Neuromuscular Disorders.13 (4):334–40.doi:10.1016/S0960-8966(02)00283-3.PMID12868503.S2CID53265571.