Regulation of Gap Junctions in Porcine Cumulus-Oocyte Complexes: Contributions of Granulosa Cell Contact, Gonadotropins, and Lipid Rafts
Bibliographic record
Abstract
Gap-junctional communication (GJC) plays a central role in oocyte growth. However, little is known about the regulation of connexin 43 (Cx43)-based gap-junction channels in cumulus-oocyte complexes (COCs) during in vitro maturation. We show that rupture of COCs from mural granulosa cells up-regulates Cx43-mediated GJC and that gonadotropins signal GJC breakdown by recruiting Cx43 to lipid rafts when oocyte meiosis resumes. Oocyte calcein uptake through gap junctions increases during early in vitro oocyte maturation and remains high until 18 h, when it falls simultaneously with the oocyte germinal vesicle breakdown. Immunodetection of Cx43 and fluorescence recovery after photobleaching assays revealed that the increase of GJC is independent of gonadotropins but requires RNA transcription, RNA polyadenylation, and translation. GJC rupture, in contrast, is achieved by a gonadotropin-dependent mechanism involving recruitment of Cx43 to clustered lipid rafts. These results show that GJC up-regulation in COCs in in vitro culture is independent of gonadotropins and transcriptionally regulated. However, GJC breakdown is gonadotropin dependent and mediated by the clustering of Cx43 in lipid raft microdomains. In conclusion, this study supports a functional role of lipid raft clustering of Cx43 in GJC breakdown in the COCs during in vitro maturation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 |
| 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".