5e6m
From Proteopedia
Crystal structure of human wild type GlyRS bound with tRNAGly
Structural highlights
Disease[SYG_HUMAN] Defects in GARS are the cause of Charcot-Marie-Tooth disease type 2D (CMT2D) [MIM:601472]. CMT2D is a form of Charcot-Marie-Tooth disease, the most common inherited disorder of the peripheral nervous system. Charcot-Marie-Tooth disease is classified in two main groups on the basis of electrophysiologic properties and histopathology: primary peripheral demyelinating neuropathy or CMT1, and primary peripheral axonal neuropathy or CMT2. Neuropathies of the CMT2 group are characterized by signs of axonal regeneration in the absence of obvious myelin alterations, normal or slightly reduced nerve conduction velocities, and progressive distal muscle weakness and atrophy. CMT2D is characterized by a more severe phenotype in the upper extremities (severe weakness and atrophy, absence of tendon reflexes) than in the lower limbs. CMT2D inheritance is autosomal dominant.[1] Defects in GARS are a cause of distal hereditary motor neuronopathy type 5A (HMN5A) [MIM:600794]; also known as distal hereditary motor neuropathy type V (DSMAV). A disorder characterized by distal muscular atrophy mainly affecting the upper extremities, in contrast to other distal motor neuronopathies. These constitute a heterogeneous group of neuromuscular diseases caused by selective degeneration of motor neurons in the anterior horn of the spinal cord, without sensory deficit in the posterior horn. The overall clinical picture consists of a classical distal muscular atrophy syndrome in the legs without clinical sensory loss. The disease starts with weakness and wasting of distal muscles of the anterior tibial and peroneal compartments of the legs. Later on, weakness and atrophy may expand to the proximal muscles of the lower limbs and/or to the distal upper limbs.[2] Function[SYG_HUMAN] Catalyzes the attachment of glycine to tRNA(Gly). Is also able produce diadenosine tetraphosphate (Ap4A), a universal pleiotropic signaling molecule needed for cell regulation pathways, by direct condensation of 2 ATPs.[3] Publication Abstract from PubMedAminoacyl-tRNA synthetases are essential components of the protein translational machinery in all living species, among which the human glycyl-tRNA synthetase (hGlyRS) is of great research interest because of its unique species-specific aminoacylation properties and noncanonical roles in the Charcot-Marie-Tooth neurological disease. However, the molecular mechanisms of how the enzyme carries out its classical and alternative functions are not well understood. Here, we report a complex structure of the wild-type hGlyRS bound with tRNAGly at 2.95A. In the complex, the flexible Whep-TRS domain is visible in one of the subunits of the enzyme dimer, and the tRNA molecule is also completely resolved. At the active site, a glycyl-AMP molecule is synthesized and is waiting for the transfer of the glycyl moiety to occur. This cocrystal structure provides us with new details about the recognition mechanism in the intermediate stage during glycylation, which was not well elucidated in the previous crystal structures where the inhibitor AMPPNP was used for crystallization. More importantly, the structural and biochemical work conducted in the current and previous studies allows us to build a model of the full-length hGlyRS in complex with tRNAGly, which greatly helps us to understand the roles that insertions and the Whep-TRS domain play in the tRNA-binding process. Finally, through structure comparison with other class II aminoacyl-tRNA synthetases bound with their tRNA substrates, we found some commonalities of the aminoacylation mechanism between these enzymes. Crystal Structure of the Wild-Type Human GlyRS Bound with tRNAGly in a Productive Conformation.,Qin X, Deng X, Chen L, Xie W J Mol Biol. 2016 May 31. pii: S0022-2836(16)30187-5. doi:, 10.1016/j.jmb.2016.05.018. PMID:27261259[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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