The Urokinase-Type Plasminogen Activator Contributes to cAMP-Induced Steroidogenesis in MA-10 Leydig Cells
Bibliographic record
Abstract
Leydig cells produce androgens which are essential for male sex differentiation and reproductive functions. Steroidogenesis, as well as expression of several genes in Leydig cells, are stimulated by LH/cAMP and repressed by AMP/AMPK. One of those genes is Plau, which codes for the urokinase-type plasminogen activator (uPA), a secreted serine protease. The role of uPA and the regulation of Plau expression in Leydig cells remain unknown. Using siRNA-mediated knockdown, uPA was required for maximal cAMP-induced STAR and steroid hormone production in MA-10 Leydig cells. Analysis of Plau mRNA levels and promoter activity revealed that its expression is strongly induced by cAMP; this induction is blunted by AMPK. The cAMP-responsive region was located, in part, in the proximal Plau promoter that contains a species-conserved GC box at −56 bp. The transcription factor Krüppel-like factor 6 (KLF6) activated the Plau promoter. Mutation of the GC box at −56 bp abolished KLF6-mediated activation and significantly reduced cAMP-induced Plau promoter activity. These data define a role for uPA in Leydig cell steroidogenesis and provide insights into the regulation of Plau gene expression in these cells.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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) | 0.000 | 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 teacher head, 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".