Biogenesis and Evolution of Functional tRNAs
13
Citation
174
Reference
10
Related Paper
Citation Trend
Keywords:
Genetic Code
Genetic Code
Code (set theory)
Position (finance)
Nucleobase
Cite
Citations (12)
The universal genetic code is a translation table by which nucleic acid sequences can be interpreted as polypeptides with a wide range of biological functions. That information is used by aminoacyl-tRNA synthetases to translate the code. Moreover, amino acid properties dictate protein folding. We recently reported that digital correlation techniques could identify patterns in tRNA identity elements that govern recognition by synthetases. Our analysis, and the functionality of truncated synthetases that cannot recognize the tRNA anticodon, support the conclusion that the tRNA acceptor stem houses an independent code for the same 20 amino acids that likely functioned earlier in the emergence of genetics. The acceptor-stem code, related to amino acid size, is distinct from a code in the anticodon that is related to amino acid polarity. Details of the acceptor-stem code suggest that it was useful in preserving key properties of stereochemically-encoded peptides that had developed the capacity to interact catalytically with RNA. The quantitative embedding of the chemical properties of amino acids into tRNA bases has implications for the origins of molecular biology.
Genetic Code
EF-Tu
Amino Acyl-tRNA Synthetases
Nucleobase
Cite
Citations (35)
Abstract Aminoacyl‐tRNA synthetases catalyse a key reaction in protein biosynthesis. They match the 20 amino acids to the genetic code by specifically attaching them to their adaptors, transfer ribonucleic acid (tRNA) molecules.
Genetic Code
Amino Acyl-tRNA Synthetases
Amino Acyl-tRNA Synthetases
Cite
Citations (17)
Genetic Code
Code (set theory)
Position (finance)
Reading frame
Cite
Citations (8)
The molecular basis of the genetic code manifests itself in the interaction of the aminoacyl-tRNA synthetases and their cognate tRNAs. The fundamental biological question regarding these enzymes' role in the evolution of the genetic code remains open. Here we probe this question in a system in which the same tRNA species is aminoacylated by two unrelated synthetases. Should this tRNA possess major identity elements common to both enzymes, this would favor a scenario where the aminoacyl-tRNA synthetases evolved in the context of preestablished tRNA identity, i.e., after the universal genetic code emerged. An experimental system is provided by the recently discovered O-phosphoseryl-tRNA synthetase (SepRS), which acylates tRNA(Cys) with phosphoserine (Sep), and the well known cysteinyl-tRNA synthetase, which charges the same tRNA with cysteine. We determined the identity elements of Methanocaldococcus jannaschii tRNA(Cys) in the aminoacylation reaction for the two Methanococcus maripaludis synthetases SepRS (forming Sep-tRNA(Cys)) and cysteinyl-tRNA synthetase (forming Cys-tRNA(Cys)). The major elements, the discriminator base and the three anticodon bases, are shared by both tRNA synthetases. An evolutionary analysis of archaeal, bacterial, and eukaryotic tRNA(Cys) sequences predicted additional SepRS-specific minor identity elements (G37, A47, and A59) and suggested the dominance of vertical inheritance for tRNA(Cys) from a single common ancestor. Transplantation of the identified identity elements into the Escherichia coli tRNA(Gly) scaffold endowed facile phosphoserylation activity on the resulting chimera. Thus, tRNA(Cys) identity is an ancient RNA record that depicts the emergence of the universal genetic code before the evolution of the modern aminoacylation systems. PMID: 17110438 Funding information This work was supported by: NIGMS NIH HHS, United States Grant ID: GM22854
Genetic Code
Amino Acyl-tRNA Synthetases
Amino Acyl-tRNA Synthetases
Aminoacylation
Selenocysteine
Methanococcus
Cite
Citations (0)
Genetic Code
Cite
Citations (8)
This chapter contains sections titled: tRNA: Structure and Function Introduction Secondary Structure Tertiary Structure tRNA Modifications Recognition of tRNA by tRNA synthetase: Identity Elements Is the tRNA Cloverleaf Structure a Pre-requisite for the L-shape? Other Functions of tRNA outside the Ribosomal Elongation Cycle Human Neurodegenerative Disorders Associated with Mitochondrial tRNAs References Aminoacylations of tRNAs: Record-keepers for the Genetic Code Introduction The Operational RNA Code Extant Aminoacyl-tRNA Synthetases The Origin of Aminoacyl-tRNA Synthetase Classes: Two Proteins bound to one tRNA A Common Genetic Origin for all Aminoacyl-tRNA Synthetases? Evolution of Extant Enzymes prior to LUCA Changes in Acceptor Stem Identity Elements Correlate with Changes in the Code References
Genetic Code
Amino Acyl-tRNA Synthetases
Cite
Citations (1)
Abstract Fidelity of tRNA charging by amino acids ensures correct translation of the genetic code into proteins. Charging is catalysed by aminoacyl‐tRNA synthetases in reactions whose specificity is ensured by positive elements, the identity determinants unique to each tRNA and responsible for its recognition by the cognate synthetase, and negative elements, the antideterminants that prevent false recognitions.
Genetic Code
Amino Acyl-tRNA Synthetases
Cite
Citations (0)
Genetic Code
Coding region
Wobble base pair
Cite
Citations (20)