Glutaminyl-tRNA synthetase is an enzyme that in humans is encoded by the QARS gene. [3] [4] [5]
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. In metazoans, 9 aminoacyl-tRNA synthetases specific for glutamine (gln), glutamic acid (glu), and 7 other amino acids are associated within a multienzyme complex. Although present in eukaryotes, glutaminyl-tRNA synthetase (QARS) is absent from many prokaryotes, mitochondria, and chloroplasts, in which Gln-tRNA(Gln) is formed by transamidation of the misacylated Glu-tRNA(Gln). Glutaminyl-tRNA synthetase belongs to the class-I aminoacyl-tRNA synthetase family. [5] Almost all eukaryotic GlnRS enzymes possess a YqeY domain at the N-terminus, which affects affinity for the tRNA; in some bacterial species, such as Deinococcus radiodurans , YqeY is present as a C-terminal domain with similar function. [6]
An aminoacyl-tRNA synthetase, also called tRNA-ligase, is an enzyme that attaches the appropriate amino acid onto its corresponding tRNA. It does so by catalyzing the transesterification of a specific cognate amino acid or its precursor to one of all its compatible cognate tRNAs to form an aminoacyl-tRNA. In humans, the 20 different types of aa-tRNA are made by the 20 different aminoacyl-tRNA synthetases, one for each amino acid of the genetic code.
Apoptosis signal-regulating kinase 1 (ASK1) also known as mitogen-activated protein kinase 5 (MAP3K5) is a member of MAP kinase family and as such a part of mitogen-activated protein kinase pathway. It activates c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases in a Raf-independent fashion in response to an array of stresses such as oxidative stress, endoplasmic reticulum stress and calcium influx. ASK1 has been found to be involved in cancer, diabetes, rheumatoid arthritis, cardiovascular and neurodegenerative diseases.
Elongation factor 1-delta is a protein that in humans is encoded by the EEF1D gene.
Elongation factor 1-alpha 1 (eEF1a1) is a translation elongation protein, expressed across eukaryotes. In humans, it is encoded by the EEF1A1 gene.
Tryptophanyl-tRNA synthetase, cytoplasmic is an aminoacyl-tRNA synthetase enzyme that attaches the amino acid tryptophan to its cognate tRNA. In humans, it is encoded by the WARS gene.
Elongation factor 1-beta is a protein that in humans is encoded by the EEF1B2 gene.
Aminoacyl tRNA synthetase complex-interacting multifunctional protein 1 is a protein that in humans is encoded by the AIMP1 gene.
Lysyl-tRNA synthetase is an enzyme that in humans is encoded by the KARS gene.
Elongation factor 1-gamma is a protein that in humans is encoded by the EEF1G gene.
Tyrosyl-tRNA synthetase, cytoplasmic, also known as Tyrosine-tRNA ligase, is an enzyme that in humans is encoded by the YARS gene.
Bifunctional aminoacyl-tRNA synthetase is an enzyme that in humans is encoded by the EPRS gene.
Arginyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the RARS gene.
Aspartyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the DARS gene.
Aminoacyl tRNA synthetase complex-interacting multifunctional protein 2 is an enzyme that in humans is encoded by the AIMP2 gene.
Leucyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the LARS gene.
Methionyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the MARS gene.
Isoleucyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the IARS1 gene.
The aminoacyl-tRNA synthetases catalyse the attachment of an amino acid to its cognate transfer RNA molecule in a highly specific two-step reaction. These proteins differ widely in size and oligomeric state, and have limited sequence homology. The 20 aminoacyl-tRNA synthetases are divided into two classes, I and II. Class I aminoacyl-tRNA synthetases contain a characteristic Rossmann fold catalytic domain and are mostly monomeric. Class II aminoacyl-tRNA synthetases share an anti-parallel beta-sheet fold flanked by alpha-helices, and are mostly dimeric or multimeric, containing at least three conserved regions. However, tRNA binding involves an alpha-helical structure that is conserved between class I and class II synthetases. In reactions catalysed by the class I aminoacyl-tRNA synthetases, the aminoacyl group is coupled to the 2'-hydroxyl of the tRNA, while, in class II reactions, the 3'-hydroxyl site is preferred. The synthetases specific for arginine, cysteine, glutamic acid, glutamine, isoleucine, leucine, methionine, tyrosine, tryptophan and valine belong to class I synthetases; these synthetases are further divided into three subclasses, a, b and c, according to sequence homology. The synthetases specific for alanine, asparagine, aspartic acid, glycine, histidine, lysine, phenylalanine, proline, serine, and threonine belong to class-II synthetases.
In molecular biology, YqeY is a type of protein domain of unknown function. It is thought to have a role in protein synthesis, facilitating the production of charged transfer RNA used in the process of translating mRNA into protein. It is present as a domain of glutaminyl-tRNA synthetase (GlnRS) in almost all eukaryotes.
Karin Musier-Forsyth, an American biochemist, is an Ohio Eminent Scholar on the faculty of the Department of Chemistry & Biochemistry at Ohio State University. Musier-Forsyth's research involves biochemical, biophysical and cell-based approaches to understand the interactions of proteins and RNAs involved in protein synthesis and viral replication, especially in HIV.