The decay phase of Ca<sup>2+</sup> transients in skeletal muscle: regulation and physiologyThis paper is one of a selection of papers published in this Special Issue, entitled 14th International Biochemistry of Exercise Conference – Muscles as Molecular and Metabolic Machines, and has undergone the Journal’s usual peer review process.
Bibliographic record
Abstract
Cytosolic Ca2+ transients associated with contraction and relaxation cycles in skeletal muscle are primarily dependent on the kinetics of Ca2+ release and Ca2+ uptake by the sarcoplasmic reticulum (SR). In humans, sarco(endo)plasmic reticulum Ca2+-ATPases (SERCAs) are solely responsible for the removal of Ca2+ from the cytosol following muscle contraction. There are several signalling systems involved in the acute regulation of SERCAs required to achieve a given Ca2+ transient during muscle contraction-relaxation cycles. Cyclic-AMP-dependent protein kinase and Ca2+/calmodulin-dependent protein kinase signalling activate SERCAs through the regulation of the endogenous SERCA-regulatory proteins, phospholamban and sarcolipin, both of which are highly expressed in human skeletal muscle. Recent studies on the regulation of SERCA2b in arterial smooth muscle and work from my laboratory on the interaction between SERCAs and the inducible 70-kDa heat shock protein suggests a novel role for redox signalling in regulating SERCA activity. In the absence of fatigue, activation of these signalling systems in response to repeated muscle activity serves to increase the rate of cytosolic free Ca2+ ([Ca2+]f) decay (i.e., SR Ca2+ uptake) and the speed of muscle relaxation.
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) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.002 |
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".