Threonine–tRNA ligase 1, cytoplasmic, also called threonyl-tRNA synthetase 1, is an enzyme that in humans is encoded by the TARS1gene. Like its relatives, TARS2 and TARS3, this enzyme functions as a threonine–tRNA ligase, which means it attaches the animo acid threonine to its corresponding transfer RNA as part of RNA-to-protein translation.
Aminoacyl tRNA synthetases catalyze the aminoacylation of tRNA by their cognate amino acid. Because of their central role in linking amino acids with nucleotide triplets contained in tRNAs, aminoacyl-tRNA synthetases are thought to be among the first proteins that appeared in evolution. Threonyl-tRNA synthetase belongs to the class-II aminoacyl-tRNA synthetase family.
Comparison with TARS3
Cytoplasmic threonine–tRNA ligase is unique in vertebrate aminoacyl-tRNA synthetases in having a second form, TARS3 (previously called TARSL2), evolved from a gene duplication. In mice, the TARS1 enzyme is significantly more prevalent (55x in lungs, and 3x in muscles). Structurally, TARS1 functions as a homodimer, while TARS3 may instead be a component of the protein complex: multisynthetase complex (MSC). TARS1 is also smaller, 83 kD vs. 93 kD, and this has been used to infer that it is the primary target of the antibodies involved in antisynthetase syndrome.
Medical significance
Pathogenic (homozygous and compound heterozygous) mutations in TARS1 are associated with trichothiodystrophy (a type of hair fragility disorder), with the type caused by TARS1 mutation designated as: nonphotosensitive trichothiodystrophy-7 (TTD7).
Gerken SC, Wasmuth JJ, Arfin SM (1986). "Threonyl-tRNA synthetase gene maps close to leucyl-tRNA synthetase gene on human chromosome 5". Somat. Cell Mol. Genet. 12 (5): 519–22. doi:10.1007/BF01539923. PMID3464105. S2CID32380159.
Pan F, Lee HH, Pai SH, Lo KY (1982). "Purification and subunit structure studies of human placental threonyl-tRNA synthetase". Int. J. Pept. Protein Res. 19 (3): 300–9. doi:10.1111/j.1399-3011.1982.tb03042.x. PMID7118399.
Pan F, Lo KY, Pai SH, Lee HH (1982). "Kinetic mechanism of threonyl-tRNA synthetase from human placenta". Int. J. Pept. Protein Res. 20 (2): 159–66. doi:10.1111/j.1399-3011.1982.tb02670.x. PMID7118437.
Ogata K, Kurahashi A, Nishiyama C, Terao K (1994). "Presence of role of the 5SrRNA-L5 protein complex (5SRNP) in the threonyl- and histidyl-tRNA synthetase complex in rat liver cytosol". Biochim. Biophys. Acta. 1218 (3): 388–400. doi:10.1016/0167-4781(94)90192-9. PMID8049265.
Maruyama K, Sugano S (1994). "Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides". Gene. 138 (1–2): 171–4. doi:10.1016/0378-1119(94)90802-8. PMID8125298.
Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, etal. (1997). "Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library". Gene. 200 (1–2): 149–56. doi:10.1016/S0378-1119(97)00411-3. PMID9373149.
Vasilescu J, Zweitzig DR, Denis NJ, etal. (2007). "The proteomic reactor facilitates the analysis of affinity-purified proteins by mass spectrometry: application for identifying ubiquitinated proteins in human cells". J. Proteome Res. 6 (1): 298–305. CiteSeerX10.1.1.401.4220. doi:10.1021/pr060438j. PMID17203973. {{cite journal}}: Cite uses deprecated parameter |citeseerx= (help)