Pac1 endonuclease and Dhp1p 5′ → 3′ exonuclease are required for U3 snoRNA termination in <i>Schizosaccharomyces pombe</i>
Bibliographic record
Abstract
Maturation of some snoRNAs is dependent on RNase III-like endonuclease-mediated transcript cleavage, which serves as an entry for the nuclear exosome complex that trims the transcript at the 3'-end. Sequence deletions suggest this cleavage in the U3 snoRNA transcripts of Schizosaccharomyces pombe can induce transcript termination. Using mutational analyses, we demonstrate that the degree of cleavage correlates closely with both RNA maturation and transcript termination. We also show that the RNase III-like endonuclease, Pac1, and the nuclear 5'-exonuclease, Dhp1p, are essential for RNA production and transcript termination, supporting a "reversed torpedoes" model in which the endonuclease cut allows 5'- and 3'-exonuclease activities access to the transcript, leading simultaneously to transcript termination in one direction and RNA maturation in the other.
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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 | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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".