The Monothiol Glutaredoxin Grx4 Exerts an Iron-Dependent Inhibitory Effect on Php4 Function
Bibliographic record
Abstract
When iron is scarce, Schizosaccharomyces pombe cells repress transcription of several genes that encode iron-using proteins. Php4 mediates this transcriptional control by specifically interacting with the CCAAT-binding core complex that is composed of Php2, Php3, and Php5. In contrast, when there is sufficient iron, Php4 is inactivated, thus allowing the transcription of many genes that encode iron-requiring proteins. Analysis by bimolecular fluorescence complementation and two-hybrid assays showed that Php4 and the monothiol glutaredoxin Grx4 physically interact with each other. Deletion mapping analysis revealed that the glutaredoxin (GRX) domain of Grx4 associates with Php4 in an iron-dependent manner. Site-directed mutagenesis identified the Cys172 of Grx4 as being required for this iron-dependent association. Subsequent analysis showed that, although the thioredoxin (TRX) domain of Grx4 interacts strongly with Php4, this interaction is insensitive to iron. Fine mapping analysis revealed that the Cys35 of Grx4 is necessary for the association between the TRX domain and Php4. Taken together, the results revealed that whereas the TRX domain interacts constitutively with Php4, the GRX domain-Php4 association is both modulated by iron and required for the inhibition of Php4 activity in response to iron repletion.
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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 | 0.000 |
| 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 | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| 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".