Early embryonic lethality caused by disruption of the gene for choline kinase alpha, the first enzyme in phosphatidylcholine biosynthesis
Bibliographic record
Abstract
Choline kinase alpha (CK‐α) is one of two mammalian choline kinase (CK) enzymes (α and β) that catalyze the phosphorylation of choline to phosphocholine in the biosynthesis of the major membrane phospholipid, phosphatidylcholine (PC). To investigate the specific role of CK‐α we created mice lacking CK‐α with a ES cell line containing an insertional mutation in the gene for CK‐α ( Chka ). Embryos homozygous for the mutant Chka allele were recovered at the blastocyst stage, but not at E7.5, indicating that CK‐α is crucial for the early development of mouse embryos. Heterozygous mutant mice ( Chka +/− ) appeared entirely normal in their embryonic development and gross anatomy and were fertile. Although CK activity was decreased by ~ 30% in the livers and testes of Chka +/− mice, the amount of PC in cells and the levels of other enzymes involved in PC biosynthesis were unaffected. Triacylglycerol and cholesterol ester were elevated ~twofold in the livers whereas neutral lipid profiles in plasma were similar in Chka +/− and wild‐type ( Chka +/+ ) mice. Enhanced levels of choline and attenuated levels of phosphocholine were observed both in liver and in testis from Chka +/− mice. Thus, Chka is an essential gene in mice, but mice do not require full expression of the gene for normal levels of PC in cells. This research was supported by a grant from the Canadian Institutes of Health Research and an NHLBI‐funded Program for Genomics Applications (“BayGenomics,” HL66621, HL66600, and HL66590)
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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 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".