Table 2.
Basal Ins(1,4,5)P3 Was >40-Fold Higher in the Hs PIPKIα Cells and Increased Further in Response to Osmotic Stress
| Cell Type | Control (pmol InsP3/g FW) | Osmotic Stress (pmol InsP3/g FW) | Fold Increase in InsP3 |
|---|---|---|---|
| NT-1 | 139 ± 57 | 3,099 ± 366 | 25.5 ± 11.0 |
| GFP | 138 ± 47 | 4,336 ± 327 | 34.6 ± 6.0 |
| At PIPK10-4 | 328 ± 125 | 3,252 ± 1,145 | 10.1 ± 0.5 |
| At PIPK10-5 | 239 ± 4 | 2,442 ± 229 | 10.2 ± 3.0 |
| Hs PIPKIα-2 | 6,457 ± 1,692 | 16,679 ± 4,598 | 2.6 ± 0.1 |
| Hs PIPKIα-3 | 5,260 ± 106 | 13,427 ± 4,893 | 3.7 ± 1.4 |
Cells (0.25 g fresh weight [FW]) were preequilibrated in 5 mL of conditioned medium and harvested at time zero (control) and 15 min after adding 0.6 osmolal sorbitol. Ins(1,4,5)P3 was quantified using the Ins(1,4,5)P3 binding assay. Data are the averages ± sd from three separate experiments.