SRC Expression and Activity Regulate Mouse Blastocyst Formation.
Bibliographic record
Abstract
The investigation of the mechanisms controlling preimplantation development is necessary to improve our assessment of embryonic development and to apply assisted reproductive technologies efficiently. The Na+/K+-ATPase plays a pivotal role during preimplantation development; the period between oocyte-sperm union and uterine wall invasion. Activity of the Na+/K+-ATPase establishes a trans-epithelial ionic gradient that facilitates the movement of water to form the fluid-filled blastocyst cavity. Reaching the blastocyst stage is necessary for implantation, and consequently, successful pregnancy. The Na+/K+-ATPase is implicated in regulating tight junction assembly and function and most recently in extracellular protein interactions. Signal transduction properties of the Na+/K+-ATPase have been discovered following binding of cardiotonic steroids (CTS), such as ouabain, to its α subunit leading to SRC activation. We hypothesize that pump activation induced by ouabain leads to SRC activation, resulting in the regulation of tight junction formation and function during mouse preimplantation development. To investigate this hypothesis, embryos were collected following application of superovulation methods to MF1 female mice. Preimplantaion embryos of the desired stage were subjected to CTS treatment or Src Family Kinase (SFK) inhibition followed by immmuofluorescence. Morula stage embryos were treated with 10-3 M, 10-5 M, 10-7 M, 10-9 M ouabain or bufalin to characterize affects of CTS treatment on blastocyst formation. Treatment with 10-5 M, 10-7 M, and 10-9 M CTS for 30 h did not significantly affect the proportion of morulae that progressed to the blastocyst stage. However, embryos treated with 10-3 M CTS did not progress to the blastocyst stage. Next experiments investigated the effects of treating blastocysts with 10-3 M, 10-4 M, and 10-5 M ouabain for 2 or 10 min to characterize influences of ouabain treatment on SRC phosphorylation by whole-mount immunofluorescence. Reduced Tyr418 phosphorylation after treatment with 10-3 M ouabain for 10 min was apparent when compared to control embryos. Next experiments treated morulae in PP2 (SFK blocker) for 18 h. Embryos treated with PP2 displayed a reversible blockade of development and did not cavitate using 20 μM, 30 μM, or 50 μM PP2. Morulae treated with SU6656, a more potent and specific SFK inhibitor, for 18hr also displayed an inability to cavitate using 1, 5, 10 μM doses. RT-PCR analysis was used to detect mRNAs encoding all SFKs during preimplantation development. mRNAs encoding SRC and YES were detectable at the blastocyst stage while mRNAs encoding FGR, LCK, LYN, FYN, HCK, and BLK were not present in blastocysts. These studies contribute to our understanding of the mechanisms controlling preimplantation development. Activation of SRC through phosphorylation of tyrosine 418 is necessary for mouse blastocyst formation. The presence of a ouabain-induced Na+/K+-ATPase signaling transduction pathway via SRC was revealed in the mouse blastocyst. Future experiments will investigate the effect of SFK inhibition on trophectoderm tight junction function. Research supported by operating grant from the Canadian Institutes of Health Research. (poster)
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 | 0.000 | 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) | 0.000 | 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".