Methionyl‐tRNA synthetase from <i>Caenorhabditis elegans</i>: A specific multidomain organization for convergent functional evolution
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Methionyl-tRNA synthetase (MetRS) is a multidomain protein that specifically binds tRNAMet and catalyzes the synthesis of methionyl-tRNAMet. The minimal, core enzyme found in Aquifex aeolicus is made of a catalytic domain, which catalyzes the aminoacylation reaction, and an anticodon-binding domain, which promotes tRNA-protein association. In eukaryotes, additional domains are appended in cis or in trans to the core enzyme and increase the stability of the tRNA-protein complexes. Eventually, as observed for MetRS from Homo sapiens, the C-terminal appended domain causes a slow release of aminoacyl-tRNA and establishes a limiting step in the global aminoacylation reaction. Here, we report that MetRS from the nematode Caenorhabditis elegans displays a new type of structural organization. Its very C-terminal appended domain is related to the oligonucleotide binding-fold-based tRNA-binding domain (tRBD) recovered at the C-terminus of MetRS from plant, but, in the nematode enzyme, this domain is separated from the core enzyme by an insertion domain. Gel retardation and tRNA aminoacylation experiments show that MetRS from nematode is functionally related to human MetRS despite the fact that their appended tRBDs have distinct structural folds, and are not orthologs. Thus, functional convergence of human and nematode MetRS is the result of parallel and convergent evolution that might have been triggered by the selective pressure to invent processivity of tRNA handling in translation in higher eukaryotes.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it