Colocalization of chaperone Cpn60, proinsulin and convertase PC1 within immature secretory granules of insulin-secreting cells suggests a role for Cpn60 in insulin processing
Bibliographic record
Abstract
Many of the mechanisms that control insulin processing and packaging by interaction with different elements along the secretory pathway remain poorly understood. We have investigated the possibility that Cpn60, a member of the heat shock protein family, may be present in rat insulin-secreting cells, participating in the proinsulin-insulin maturation process. Immunofluorescence and high resolution immunocytochemical studies revealed the presence of the Cpn60 protein all along the insulin secretory pathway, being particularly abundant over the proinsulin-containing immature secretory granules. Double-labeling experiments showed associations between Cpn60 and proinsulin, as well as between Cpn60 and PC1 convertase, with a preferential binding to proinsulin. These findings paralleled those of coimmunoprecipitation studies showing the Cpn60 chaperone and the mature form of the PC1 convertase in proinsulin immunoprecipitates, as well as the PC1 in Cpn60 immunoprecipitates from total islet cell extracts. In vitro binding of Cpn60 to proinsulin, insulin and glucagon was also documented. Cpn60, significantly abundant in proinsulin-containing secretory granules where conversion of proinsulin to insulin takes place, and the colocalization of the chaperone with proinsulin and PC1 convertase suggest that the Cpn60 protein may play a role directing precise molecular interactions during insulin processing and/or packaging.
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 | 0.000 |
| 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".