Role of the membrane cholesterol-glycosphingolipid complex as a ‘transistor’ to regulate GSL receptor function and signaling of both lipids
Bibliographic record
Abstract
Abstract Cholesterol and glycosphingolipids (GSL) are the major species that accumulate in plasma membrane lipid rafts. These complexes imbue the membrane with increased order, which in turn, plays a central role in the transmembrane signaling foci lipid rafts provide. In addition, both GSL and cholesterol binding can mediate (separate) signal pathways. We have shown that cholesterol and GSLs however, form a complex in which the GSL sugar is reoriented from a membrane perpendicular to parallel format, becoming largely unavailable for exogenous ligand binding. Similarly, the steroid hydroxyl is masked, restricting access of cholesterol ligands. This was observed in model and cell membranes and in human tumour frozen tissue sections. We now show the order of exogenous ligand binding plays a significant role to determine the extent of GSL or cholesterol receptor activity. Ligand binding to cholesterol enhances subsequent GSL recognition and vice versa, suggesting that ligand binding to “free” receptor (membrane perpendicular GSL carbohydrate, nonmasked cholesterol) can result in partial dissociation of the GSL/cholesterol complex to allow additional GSL ligand and cholesterol ligand binding. Since many GSLs can complex with membrane cholesterol, the binding of a single cholesterol ligand may unmask cholesterol-complexed GSL for increased binding of both a single or multiple GSL-specific ligands. We show that multiple cholesterol-masked GSLs can be coincident in tissues. This provides a mechanism for GSL-dependent signal amplification and diversification, representing a biological ‘transistor’, regulating amplitude and potentially, diversity of GSL signaling. The process represents a new mechanism of ‘cross-talk’ between GSL and cholesterol signaling. This is of clinical importance since we have found cholesterol/GSL masking applies to monoclonal anti GSL antibodies in development and in current use as antineoplastic therapeutics.
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 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".