Cardiac CapZ Regulation During Acute Exercise in Female Mice
Bibliographic record
Abstract
Exercise requires a rapid cardiac response to maintain cardiovascular function. CapZ is a critical stress-response protein in cardiac myocytes. While its role in the pathological stress response has been explored, its part in the physiological response to exercise is unknown. This study examined CapZ regulation during exercise to determine its importance in the cardiac response. Female wildtype or cardiac CapZ-deficient transgenic mice ("CapZ mice") were subjected to exhaustive swimming or running protocols and submaximal running. Time to exhaustion was a measurement of exercise capacity. Following submaximal exercise, cardiac myofilaments were isolated and probed for CapZ, its regulatory proteins, and myofilament proteins. Myofilament function was assessed using an actomyosin MgATPase assay, and protein phosphorylation was quantified with ProQ Diamond staining. Total myofilament CapZ was unaffected by exercise, but increased CapZIP and decreased phosphorylated CapZIP indicated weakened CapZ-actin interaction. Myofilaments from CapZ mice lacked changes in CapZIP. Time to exhaustion was lower in CapZ mice in both swimming and running protocols. Actomyosin MgATPase activity was maintained in wildtype mice and impaired with CapZ deficiency. Exercise increased myofilament protein phosphorylation in wildtype mice but not in transgenic animals. Exercise-dependent increases in myofilament PKC-α and -ε were mitigated in CapZ mice. Telethonin/Tcap levels decreased significantly in CapZ-deficient myofilaments with exercise, and leiomodin 2 increased in wildtype myofilaments. These data show Cardiac CapZ is a critical player in the physiological response to exercise and that CapZ-actin binding is rapidly altered with exercise. Decreased cardiac CapZ limits exercise capacity, impairs myofilament regulation, and leads to a less stable contractile apparatus.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 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) | 0.000 | 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 teacher head, 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".