1q11
Crystal structure of an active fragment of human tyrosyl-tRNA synthetase with tyrosinol
Structural highlights
DiseaseSYYC_HUMAN Defects in YARS are the cause of Charcot-Marie-Tooth disease dominant intermediate type C (CMTDIC) [MIM:608323. CMTDIC is a form of Charcot-Marie-Tooth disease characterized by clinical and pathologic features intermediate between demyelinating and axonal peripheral neuropathies, and motor median nerve conduction velocities ranging from 25 to 45 m/sec.[1] FunctionSYYC_HUMAN Catalyzes the attachment of tyrosine to tRNA(Tyr) in a two-step reaction: tyrosine is first activated by ATP to form Tyr-AMP and then transferred to the acceptor end of tRNA(Tyr) (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedEarly forms of the genetic code likely generated "statistical" proteins, with similar side chains occupying the same sequence positions at different ratios. In this scenario, groups of related side chains were treated by aminoacyl-tRNA synthetases as a single molecular species until a discrimination mechanism developed that could separate them. The aromatic amino acids tryptophan, tyrosine, and phenylalanine likely constituted one of these groups. A crystal structure of human tryptophanyl-tRNA synthetase was solved at 2.1 A with a tryptophanyl-adenylate bound at the active site. A cocrystal structure of an active fragment of human tyrosyl-tRNA synthetase with its cognate amino acid analog was also solved at 1.6 A. The two structures enabled active site identifications and provided the information for structure-based sequence alignments of approximately 45 orthologs of each enzyme. Two critical positions shared by all tyrosyl-tRNA synthetases and tryptophanyl-tRNA synthetases for amino acid discrimination were identified. The variations at these two positions and phylogenetic analyses based on the structural information suggest that, in contrast to many other amino acids, discrimination of tyrosine from tryptophan occurred late in the development of the genetic code. Crystal structures that suggest late development of genetic code components for differentiating aromatic side chains.,Yang XL, Otero FJ, Skene RJ, McRee DE, Schimmel P, Ribas de Pouplana L Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15376-80. Epub 2003 Dec 11. PMID:14671330[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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