Table 3.
Composition (% GPI1-A) of E12.5 3n↔2n and 2n↔2n chimeric conceptuses.
| Epiblast derivatives | Primitive endoderm derivatives | Trophectoderm derivatives | |||||
|---|---|---|---|---|---|---|---|
| Chimera | Fetus | Amnion | YS mes | YS end | P end | Troph (RM) | Placenta |
| 3n↔2n chimeras (uncorrected %GPI1-A)a | |||||||
| TrA-16 | 0.0 | 6.7 | 10.9 | 50.7 | 50.9 | 27.7 | 14.4 |
| TrA-26 | 0.0 | 0.0 | 0.0 | 28.3 | 25.7 | 0.0 | 0.0 |
| Mean±s.e.m. | 0.0±0 | 3.4±3.4 | 5.5±5.5 | 39.5±11.2 | 38.3±12.6 | 13.9±13.9 | 7.2±7.2 |
| 3n↔2n chimeras (corrected %GPI1-A)a,b | |||||||
| TrA-16 | 0.0 | 4.6 | 7.5 | 40.7 | 40.9 | 20.3 | 10.1 |
| TrA-26 | 0.0 | 0.0 | 0.0 | 20.8 | 18.7 | 0.0 | 0.0 |
| Mean±s.e.m. | 0.0±0 | 2.3±2.3 | 3.8±3.8 | 30.8±9.9 | 29.8±11.1 | 10.2±10.2 | 5.0±5.0 |
| 2n↔2n chimeras (N=25)c | |||||||
| Mean±s.e.m. | 47.0±3.6 | 47.1±3.8 | 45.8±3.6 | 56.5±3.3 | 62.2±4.8 | 45.1±7.7 | 42.1±7.1 |
YS mes, visceral yolk sac mesoderm; YS end, visceral yolk sac endoderm; P end, parietal endoderm; Troph (RM), trophoblast overlying Reichert's membrane.
a
Recipient females were Gpi1c/c, so any maternal contribution (GPI1-C) was excluded from the analysis.
b
The corrected %GPI1-A=⅔A×100/(⅔A+B), where A=%GPI1-A and B=%GPI1-B. This allows for the expectation that 3n cells would produce 1.5 times the GPI1 activity of 2n cells and probably provides a closer estimate of the percentage 3n cells.
c
Conceptus TrA-6 was not classified as 3n↔2n or 2n↔2n and is excluded from the table. (It had 15.9% GPI1-A in the yolk sac mesoderm and 0% GPI1-A in the other four tissues analysed.)