Table 2.
Generation of puromycin-resistant variants from mouse cell lines without drug-resistance genes
| Cells | Percent
resistance to puromycin*
|
||
|---|---|---|---|
| 2.5 μg of puromycin second selection | 5 μg of puromycin second selection | 20 μg of puromycin after multiple selections | |
| 771, Mdr1a,b−/− | 50† | <2 (few colonies) | >90 |
| 886, Mdr1a,b−/− | 50 | <2 (few colonies) | >90 |
| 4B, Mdr1a,b−/−, Mrp1−/− | <10 (colonies) | 0 | >90 |
| WT-2ac1, wild type | >90 | >90 | >90 (3 selections) |
| WT-12, wild type | >90 | 75 | >90 (3 selections) |
*
2–4 million cells were seeded per 10-cm dish and treated the next day.
†
Resistances, reported as percent confluence of a drug-treated culture by the time an untreated control had become confluent, were recorded 9–16 days after initiation of drug treatments. Low percentages of resistance manifest as isolated colonies.