Receptor of activated C kinase 1 (RACK1) is necessary for the 20‐hydroxyecdysone‐induced expression of the transcription factor CHR3 in the spruce budworm <i>Choristoneura fumiferana</i>
Bibliographic record
Abstract
To initiate moulting and metamorphosis, 20-hydroxyecdysone (20E) binds to its nuclear receptors and the ligand-receptor complex then mediates changes in gene expression. Phosphorylation of the receptors is required for their function. The intracellular signal transduction pathway that is involved in receptor phosphorylation remains elusive. This study provides evidence that the receptor of activated C kinase 1 (RACK1) and protein kinase C (PKC) signal transduction cascade is involved in the 20E-induced expression of the moult-associated transcription factor CHR3. A cDNA clone encoding a receptor of activated C kinase 1 was isolated from Choristoneura fumiferana (CfRACK1). This single copy gene coded a 36 kDa protein and was expressed ubiquitously in all of the developmental stages and the tissues tested, including the midgut, epidermis, fat body, head, Malpighian tubules, ovary and testis of larvae. High levels of the transcripts were also detected in a midgut-derived CF-203 cell line. We noticed that the green fluorescence protein-fused CfRACK1 protein was distributed in the cytosol surrounding the nuclei in stably transformed cells. Interference of CfRACK1 mRNA suppressed the 20E-induced expression of the transcription factor CHR3. Dequalinium-14; 1,1'-decamethylenebis-4-aminoquinaldinium diiodide (DECA), an inhibitor of RACK1 binding to protein kinase C, blocked the 20E-induced expression of CHR3 and accumulation of the ecdysone receptor (EcR) in the nuclei. All of these data together suggest that 20E-induced expression of CHR3 may involve phosphorylation of the ecdysone receptor component through the PKC/RACK1 signal transduction cascade, which facilitates the import of the receptor into the nuclei of cells.
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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 | 0.000 |
| 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".