Bibliographic record
Abstract
Abstract The term ‘ ribonucleic acid (RNA) editing’ describes a variety of mechanistically unrelated biochemical activities that alter RNA molecules after transcription by addition, deletion or substitution of nucleotides. Examples include insertion and deletion of uridine residues in the mitochondrial messenger RNAs (mRNAs) of kinetoplastid protozoa; cytidine‐to‐uridine deamination of specific residues in the mitochondrial mRNAs and transfer RNAs (tRNAs) of land plants; conversion of adenosine to inosine via deamination in the nuclear transcripts of metazoan animals; and replacement of nonbase‐paired nucleotides at the 5′ and 3′ ends of certain mitochondrial tRNAs. A three‐stage ‘constructive neutral evolution’ (CNE) model, illustrated by specific examples, can explain in a general way how RNA‐editing systems might arise and become fixed. The CNE model proposes that potential editing systems arise before there is an actual requirement for editing, thereby serving to relax functional constraints at the genome level because harmful/lethal mutations are able to be reversed at the level of the corresponding transcript. Key Concepts: RNA editing is a process (typically post‐transcriptional) that alters the nucleotide sequence of an RNA molecule relative to the corresponding gene sequence. Two general types of RNA editing are recognised: (1) insertional, in which nucleotides are added to (and also deleted from) internal positions and (2) substitutional, in which one nucleotide type replaces another at particular positions. All types of cellular RNA (messenger, transfer and ribosomal) may undergo editing, as well as intron, noncoding and viral sequences. RNA‐editing systems are almost exclusively restricted to eukaryotes, and are especially prominent in chloroplasts and mitochondria. RNA‐editing systems are clearly derived traits, arising relatively recently within particular eukaryotic lineages. RNA‐editing systems are mechanistically diverse and biochemically distinct, pointing to numerous separate evolutionary origins. A ‘constructive neutral evolution’ (CNE) model provides a general explanation for the emergence of diverse RNA‐editing systems. A basic tenet of the CNE model is that potential RNA‐editing systems arise before there is a need for editing. The emergence of an RNA‐editing system allows fixation of otherwise deleterious mutations that can be ‘repaired’ by RNA editing.
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.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".