Table 3.
Characterization of p21 elutriated fractions
| Cell fraction* | G1, %† | S, %† | G2, %† | B+, %‡ | C, %§ |
|---|---|---|---|---|---|
| 66 (1) | 93.7 | 6.3 | 0 | 96 | 97 |
| 66 (3) | 93.7 | 6.3 | 0 | 97 | 99 |
| 70 (2) | 94.8 | 4 | 1.1 | 99 | 98 |
| 78 (2) | 0 | 98.8 | 1.2 | 1 | 1 |
| 90 (1) | 0 | 99.9 | 0.1 | 1 | 2 |
| 94 (1) | 0 | 99.9 | 0.1 | 2 | 2 |
| 98 (1) | 4.2 | 38.8 | 56.7 | 2 | 3 |
| 98 (2) | 2.6 | 50.6 | 46.8 | 2 | 1 |
| 106 (1) | 2.4 | 52.7 | 45.5 | 1 | 2 |
p21 MEL cell transfectant cells (p21.12) were treated with doxycycline for 36 h, and cells were separated by size by centrifugal elutriation as described in Materials and Methods. The number indicates the pump speed at which the fractions were elutriated. Several fractions were collected at each pump speed, and the number of the fraction is indicated in parentheses. Cells were resuspended at 1 × 105 cells per ml in normal growth medium and incubated at 37°C.
Percentage of cells in the indicated phase of the cell cycle was determined by fluorescence-activated cell sorter scan analysis as described in Materials and Methods immediately after elutriation.
Percentage of benzidine-positive (B+, %) cells was determined as described in Materials and Methods on aliquots of cells incubated for 5 days after elutriation.
Percentage of cells committed to terminal differentiation (C, %) was determined by plasma clot assay as described in Materials and Methods on aliquots of cells incubated for 4 days after elutriation.