Table 2.
Quantitation of Transcription Sites (TS) in the Mouse 3T3 Fibroblast Cell Nucleus
| Nuclear regions | No. of TS per confocal section | Percent distribution | Relative concentration TS/area | |
|---|---|---|---|---|
| Area | TS | |||
| Total | 418 ± 28 | 100 | 100 | 1 |
| Nucleolar | 25 ± 4.0 | 9.7 | 6 | 0.6 |
| Total extranucleolar | 393 ± 25. | 90.3 | 94 | 1 |
| Nonspeckle extranucleolar | 215 ± 25 | 81.3 | 51.4 | 0.6 |
| Speckle | 178 ± 26 | 8.7 | 42.6 | 4.9 |
| Pereipheral speckle | 114 ± 15 | — | 27.3 | — |
| Internal speckle | 64 ± 13 | — | 15.3 | — |
Values represent the average + SEM for midplane optical sections from different nuclear samples. Over 4,000 transcription sites were counted along with 214 speckles.