Ribosome Structure, Function, and Early Evolution

• Published in: International journal of molecular sciences 2018-12, Vol.20 (1), p.40
• Main Authors: Opron, Kristopher, Burton, Zachary F
• Format: Article
• Language: English
• Subjects: Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Binding sites; Chains; coevolution; EF-G; EF-Tu; Evolution; Evolution, Molecular; genetic code; Guanosine diphosphate; Guanosine triphosphate; Homology; IF2; Molecular motors; Molecular structure; mRNA; Peptide Chain Elongation, Translational - physiology; Peptide Chain Initiation, Translational - physiology; Peptide Elongation Factor Tu - chemistry; Peptide Elongation Factor Tu - genetics; Peptide Elongation Factor Tu - metabolism; Peptides; Protein Biosynthesis - physiology; Proteins; Review; ribosome; Ribosomes - chemistry; Ribosomes - metabolism; RNA, Messenger - chemistry; RNA, Messenger - genetics; RNA, Messenger - metabolism; RNA, Transfer - chemistry; RNA, Transfer - genetics; RNA, Transfer - metabolism; rRNA 16S; Structure-function relationships; Thermus thermophilus - physiology; translation elongation; translation initiation; translocation
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20010040

Ribosomes are among the largest and most dynamic molecular motors. The structure and dynamics of translation initiation and elongation are reviewed. Three ribosome motions have been identified for initiation and translocation. A swivel motion between the head/beak and the body of the 30S subunit was observed. A tilting dynamic of the head/beak versus the body of the 30S subunit was detected using simulations. A reversible ratcheting motion was seen between the 30S and the 50S subunits that slide relative to one another. The 30S⁻50S intersubunit contacts regulate translocation. IF2, EF-Tu, and EF-G are homologous G-protein GTPases that cycle on and off the same site on the ribosome. The ribosome, aminoacyl-tRNA synthetase (aaRS) enzymes, transfer ribonucleic acid (tRNA), and messenger ribonucleic acid (mRNA) form the core of information processing in cells and are coevolved. Surprisingly, class I and class II aaRS enzymes, with distinct and incompatible folds, are homologs. Divergence of class I and class II aaRS enzymes and coevolution of the genetic code are described by analysis of ancient archaeal species.