MT-TG

Jump to navigation Jump to search
mitochondrially encoded tRNA glycine
Identifiers
SymbolMT-TG
Alt. symbolsMTTG
Entrez4563
HUGO7486
RefSeqNC_001807
Other data
LocusChr. MT [1]

Mitochondrially encoded tRNA glycine also known as MT-TG is a transfer RNA which in humans is encoded by the mitochondrial MT-TG gene.[1]

Structure

The MT-TG gene is located on the p arm of the mitochondrial DNA at position 12 and it spans 68 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]

Function

MT-TG is a small 68 nucleotide transfer RNA (human mitochondrial map position 9991-10058) that transfers the amino acid glycine to a growing polypeptide chain at the ribosome site of protein synthesis during translation.

Clinical significance

Myoclonic epilepsy with ragged-red fibers (MERRF)

Mutations in transfer RNAs have been found to lead to marked mitochondrial energy deficiency and a hindrance of mitochondrial proliferation, and defects in oxidative phosphorylation. Such defects may result in myoclonic epilepsy with ragged-red fibers (MERRF). Myoclonic epilepsy with ragged-red fibers (MERRF) is a rare mitochondrial disorder that affects many parts of the body, particularly the muscles and nervous system. In most cases, the signs and symptoms of this disorder appear during childhood or adolescence. The features of MERRF vary widely among affected individuals, even among members of the same family. Common clinical manifestations include myoclonus, myopathy, spasticity,epilepsy, peripheral neuropathy, dementia, ataxia, atrophy and more.[4][5]

Familial hypertrophic cardiomyopathy

Mutations in the MT-TG gene has also been associated with familial hypertrophic cardiomyopathy. Familial hypertrophic cardiomyopathy is a heart condition characterized by thickening of the heart, usually in the interventricular septum. Common phenotypes include chest pain, shortness of breath, physical exertion, palpitations, lightheadedness, dizziness and fainting.[6] A family with a transition mutation of 9997T>C in the MT-TG gene exhibited familial hypertrophic cardiomyopathy.[7]

References

  1. 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. doi:10.1038/290457a0. PMID 7219534.
  2. "MT-TG mitochondrially encoded tRNA glycine [Homo sapiens (human)] - Gene - NCBI". www.ncbi.nlm.nih.gov.
  3. "tRNA / transfer RNA | Learn Science at Scitable". www.nature.com.
  4. "Myoclonic epilepsy with ragged-red fibers". Genetics Home Reference. U.S. National Library of Medicine.
  5. Graham BH, Waymire KG, Cottrell B, Trounce IA, MacGregor GR, Wallace DC (July 1997). "A mouse model for mitochondrial myopathy and cardiomyopathy resulting from a deficiency in the heart/muscle isoform of the adenine nucleotide translocator". Nature Genetics. 16 (3): 226–34. doi:10.1038/ng0797-226. PMID 9207786.
  6. "Familial hypertrophic cardiomyopathy". Genetics Home Reference. U.S. National Library of Medicine.
  7. Merante F, Tein I, Benson L, Robinson BH (September 1994). "Maternally inherited hypertrophic cardiomyopathy due to a novel T-to-C transition at nucleotide 9997 in the mitochondrial tRNA(glycine) gene". American Journal of Human Genetics. 55 (3): 437–46. PMID 8079988.

Further reading

  • Bidooki SK, Johnson MA, Chrzanowska-Lightowlers Z, Bindoff LA, Lightowlers RN (June 1997). "Intracellular mitochondrial triplasmy in a patient with two heteroplasmic base changes". American Journal of Human Genetics. 60 (6): 1430–8. doi:10.1086/515460. PMID 9199564.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.