The Canadian Prairie Plant Thermopsis Rhombifolia Contains Luteolin, a Flavone that Inhibits Cyclin Dependent Kinase 9 and Arrest Cells in the G1-Phase of the Cell Cycle
Bibliographic record
Abstract
Abstract INTRODUCTION: Plant species within the prairie ecological zone of Canada are a source of natural products with important bio-activities. Investigation of these plants and the secondary metabolites that they produce will provide insight into their biology, and identify sources of natural products that may become new medicines or scientific tools. METHODS: We investigated a G1 phase arrest activity in extracts from the prairie plant, Thermopsis rhombifolia (Buffalo bean) by biology-guided fractionation and isolated luteolin. Cell based assays and CETSA were used to identify a cyclin-dependent kinase 9 inhibitory activity. RESULTS AND DISCUSSION: Luteolin treated cells showed decreased phosphorylation of the carboxy terminal domain of RNA polymerase II, and low levels of Mcl-1. Plant extracts or luteolin inhibited Cdk9 (cyclin dependent kinase) in tests in vitro, stabilized Cdk9 as determined by the cellular thermal shift assay (CETSA), and arrested cells in the G1 phase of the cell cycle. CONCLUSIONS: Luteolin joins an increasing number of flavonoid inhibitors that make convenient cell biology tools and contribute to our understanding of natural product biology in plants.
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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 | 0.000 |
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".