The Ryanodine Receptor: Arrhythmias and Muscle Disorders at High Resolution
Bibliographic record
Abstract
Calcium ions play crucial roles in our bodies, acting as second messengers in multiple signaling pathways. The resting calcium levels in the cytosol are very low, but can increase rapidly and transiently by influx from the extracellular space, or by release from intracellular stores. The Endoplasmic and Sarcoplasmic Reticulum (ER/SR) form major intracellular calcium stores. The `Ryanodine Receptor' (RyR) is a protein that dictates calcium release from the ER/SR. It forms a huge ion channel with a molecular weight exceeding 2 MegaDalton. RyRs are expressed in multiple cell types, but are particularly abundant in cardiac and skeletal muscle, where they are directly involved in excitation-contraction coupling. Three RyR isoforms exist in mammalian species (RyR1, RyR2, RyR3). Mutations in RyR1 and RyR2 have been linked to a number of devastating genetic disorders, including stress-induced cardiac arrhythmias (CPVT), malignant hyperthermia, and central core disease. In the past 5 years we have been solving crystal structures of several RyR domains. Cryo-electron microscopy structures have helped us to build pseudo-atomic models, allowing us to locate these domains in full-length RyRs. Over 80 disease mutations are scattered throughout the structures. The bulk of these affect domain-domain interactions. By comparing the RyR in the open and closed state, we find that some of these interactions are labile: they are disrupted during channel opening. Many disease mutations weaken these interactions, leading to facilitated channel opening, resulting in premature or prolonged release of calcium. In addition, many other disease mutations affect the same labile interactions allosterically. Stabilizing the closed-state domain-domain interactions may therefore be of therapeutic value.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.004 |
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".