EC Number   |
General Information |
Reference |
|---|
    6.1.1.1 | physiological function |
aa-tRNA synthesis is a two-step reaction: activation of an amino acid with ATP to form aminoacyl adenylate, followed by transfer of the aminoacyl moiety to the 3' end of the tRNA. The error rate of this first step of translation is largely dependent on the specificity of the aaRS, that is selection of the correct amino acid and tRNA from the respective cellular pools of predominantly noncognate substrates. aaRSs select their cognate tRNAs by exploiting sequence-specific differences between various tRNAs during binding and aminoacylation. Translation of Tyr codons is highly prone to Phe isincorporation during amino acid limitation inCHOcells. CHO cell TyrRS is error-prone and readily aminoacylates tRNATyr with Phe, cf. EC 6.1.1.20. Steady-state kinetic analyses of CHO cytoplasmic tyrosyl-tRNA synthetase reveals a 25fold lower specificity for Tyr over Phe as compared with previously characterized bacterial enzymes, consistent with the observed increase in translation error rates during tyrosine limitation |
745300 |
| 6.1.1.1 | physiological function |
although native TyrRS has no known cytokine functions, natural proteolysis of secreted TyrRS releases TyrRSMini, which not only has the same aminoacylation activity as native TyrRS when occuring as a dimer, the monomer is inactive, but TyrRSMini also has strong activity for stimulating migration of polymorphonuclear leukocytes. The migration-stimulating activity is dependent on an ELR tripeptide motif, similar to that in CXC cytokines like IL-8, and also has the familiar bell-shaped concentration dependence seen for CXC cytokines. But TyrRSMini does not induce internalization of CXCR1/2. The TyrRSMini monomer is an agonist, while TyrRSMini dimer is an antagonist of induced PMN cell migration |
715585 |
| 6.1.1.1 | physiological function |
aminoacyl-tRNA synthetases (aaRSs) are housekeeping enzymes essential for protein synthesis. Apart from their parent aminoacylation activity, several aaRSs perform non-canonical functions in diverse biological processes. Leishmania tyrosyl-tRNA synthetase (LdTyrRS) performs aminoacylation and acts as a mimic of host CXC chemokine. Non-canonical function of Leishmania donovani tyrosyl-tRNA synthetase. The enzyme is essential. The released, extracellular LdTyrRS functions as a neutrophil chemoattractant. LdTyrRS specifically binds to host macrophages with its ELR (Glu-Leu-Arg) peptide motif. The ELR-CXCR2 receptor interaction mediates this binding. This interaction triggers enhanced secretion of the proinflammatory cytokines TNF-alpha and interleukin-6 by host macrophages. Possible immunomodulating role of LdTyrRS in Leishmania infection. Triggering of cytokine secretion by LdTyrRS, overview |
-, 745348 |
| 6.1.1.1 | physiological function |
aminoacyl-tRNA synthetases (aaRSs) for glycine, alanine, serine and tyrosine play important roles in fibroin synthesis |
746475 |
| 6.1.1.1 | physiological function |
CYT-18 also promotes self-splicing of group I intron RNAs by stabilizing the functional structure in the conserved core |
705174 |
| 6.1.1.1 | physiological function |
the flexibility and rapid dynamics of the wild-type aminoacyl-tRNA synthetase catalytic loop structure are crucial for formation of protein-substrate interactions and subsequently for overall enzyme functional activity, dynamic properties of the enzyme, overview |
-, 744822 |
| 6.1.1.1 | physiological function |
the human TyrRS can be split into two fragments with distinct signaling activities. The N-terminal fragment is an IL-8-like cytokine whereas the C-terminal fragment is more similar to endothelial monocyte-activating polypeptide II (EMAP II). Therapeutic effect of recombinant human tyrosyl-tRNA synthetase (rhTyrRS) against development of thrombocytopenia in cyclophosphamide (CTX) treated mice. Recombinant hTyrRS promotes migration and aggregation of megakaryocytes to the bone marrow niche. 1 is particularly important for the adhesion. The N-terminal fragment of the recombinant TyrRS acts as a chemoattractant molecule for M-07e cells, it stimulates adhesion of THP-1 cells to HUVECs and plays a role in the transendothelial migration of megakaryocytes and thrombocytopoiesis. All mice pretreated with rhTyrRS show a dose-dependent increase in megakaryocytes localized to the sinusoids. Recombinant human TyrRS enhances survival of cyclophosphamide (CTX) treated mice, that the bone marrow endothelial cells may enhance survival of megakaryocytes in the presence of rhTyrRS pretreatment |
744846 |
| 6.1.1.1 | physiological function |
tyrosyl-tRNA synthetase functions in group I intron splicing |
714246 |
| 6.1.1.1 | physiological function |
tyrosyl-tRNA synthetase is a potential kyotorphin synthetase (i.e. tyrosine-arginine ligase, EC 6.3.2.24) in mammals |
745971 |
