3vmf | pdb_00003vmf
Archaeal protein
Structural highlights
Function[EF1A_AERPE] This protein promotes the GTP-dependent binding of aminoacyl-tRNA to the A-site of ribosomes during protein biosynthesis (By similarity). [RF1_AERPE] Directs the termination of nascent peptide synthesis (translation) in response to the termination codons UAA, UAG and UGA (By similarity). Publication Abstract from PubMedWhen a stop codon appears at the ribosomal A site, the class I and II release factors (RFs) terminate translation. In eukaryotes and archaea, the class I and II RFs form a heterodimeric complex, and complete the overall translation termination process in a GTP-dependent manner. However, the structural mechanism of the translation termination by the class I and II RF complex remains unresolved. In archaea, archaeal elongation factor 1 alpha (aEF1alpha), a carrier GTPase for tRNA, acts as a class II RF by forming a heterodimeric complex with archaeal RF1 (aRF1). We report the crystal structure of the aRF1.aEF1alpha complex, the first active class I and II RF complex. This structure remarkably resembles the tRNA.EF-Tu complex, suggesting that aRF1 is efficiently delivered to the ribosomal A site, by mimicking tRNA. It provides insights into the mechanism that couples GTP hydrolysis by the class II RF to stop codon recognition and peptidyl-tRNA hydrolysis by the class I RF. We discuss the different mechanisms by which aEF1alpha recognizes aRF1 and aPelota, another aRF1-related protein and molecular evolution of the three functions of aEF1alpha. Structural basis for translation termination by archaeal RF1 and GTP-bound EF1alpha complex.,Kobayashi K, Saito K, Ishitani R, Ito K, Nureki O Nucleic Acids Res. 2012 Jul 5. PMID:22772989[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
