Isolation and molecular analysis of two <i>R2R3-MYB</i> genes from the sunflower (<i>Helianthus</i> <i>annuus</i>)
Bibliographic record
Abstract
MYB factors comprise one of the largest family of transcription factors (TFs) characterized by a highly conserved DNA-binding domain: the MYB domain. From the sunflower (Helianthus annuus L.) genome, we have isolated two R2R3-type MYB TFs (Ha-R2R3-MYB1 and Ha-R2R3-MYB2) that show homology with the functional domain of most R2R3-MYB proteins of other species. The R2 (53 amino acids) and R3 (51 amino acids) motifs of the sunflower MYB TFs contain typical amino acids, including a series of highly conserved tryptophan residues, which play a key role in sequence-specific DNA binding. In the MYB domain, both genes (Ha-R2R3-MYB1 and Ha-R2R3-MYB2) exhibit the highly conserved splicing arrangement of three exons and two introns. Using in situ hybridization, a weak level of Ha-R2R3-MYB1 transcription was uniformly spread in shoot apical meristem (SAM), as well as in axillary meristem (AM). By contrast, Ha-R2R3-MYB2 transcription was strongly restricted to a small domain within the boundary zone separating the SAM and the leaf primordia, suggesting that Ha-R2R3-MYB2 may be involved in an early step of AM development.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| 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 | 0.001 |
| 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".