Table 3.
Phosphoinositide levels in triple phosphatase deletion mutants and temperature sensitive mutants
| Strain | PI(3)P | PI(4)P | PI(3,5)P2 | PI(4,5)P2 |
|---|---|---|---|---|
| ymr1Δsjl3Δsjl1Δ | 3.88 (.07) | 1.04 (.18) | 0.08 (.01) | 1.69 (.08) |
| ymr1Δsjl3Δfig4Δ | 3.94 (.10) | 1.44 (.02) | 0.10 (.03) | 0.93 (.04) |
| ymr1Δsjl2Δsjl3Δ | Lethal | |||
| ymr1Δsjl2Δsjl3Δ (sjl2-8ts) 26°C | 5.56 (.38) | 1.20 (.46) | 0.12 (.02) | 0.87 (.06) |
| ymr1Δsjl2Δsjl3Δ (sjl2-8ts) 38°Ca | 6.90 (.38) | 1.32 (.32) | 0.97 (.07) | 0.91 (.06) |
| ymr1Δsjl3Δ 38°C | 4.89 (.40) | 1.52 (.30) | 0.37 (.08) | 1.03 (.35) |
| SEY6210 38°C | 1.84 (.23) | 1.76 (.15) | 0.24 (.03) | 1.74 (.25) |
Strains were labeled with myo-[3H]inositol, and lipids were extracted and processed for HPLC analysis as described in MATERIALS AND METHODS. The mean peak area (cpm) is expressed as percentage of total 3H-labeled PIs. Results are the mean ± standard deviation of at least two independent experiments done in duplicate.
a
Greater than 90% of the cells in these cultures remained viable in the time course of these experiments as determined by incorporation of the vital dye CMAC (our unpublished data). Therefore, the levels of 3′ phosphoinositides that result in loss of viability are likely to be underestimated in this analysis