Table 1.
Accumulation of PSKs in media conditioned by control or transgenic Oc cells
| Cell line | Fresh weight | PSK-α | PSK-β | [Ser4]PSK-α | [Ser4]PSK-β |
|---|---|---|---|---|---|
| C1 | 9.6 ± 1.1 | 12.6 ± 1.1 | 332.7 ± 20.1 | 0 | 0 |
| A2 | 5.1 ± 0.9 | 7.3 ± 0.4 | 175.8 ± 15.4 | 0 | 0 |
| A2 + PSK | 7.9 ± 1.5 | UD | UD | UD | UD |
| S2 | 16.2 ± 2.7 | 21.0 ± 1.9 | 555.7 ± 31.1 | 0 | 0 |
| T1 | 12.3 ± 1.9 | 11.5 ± 0.9 | 302.5 ± 15.8 | 3.1 ± 0.3 | 105.2 ± 8.9 |
Control (C1) or transformed Oc cells (0.8 g) were transplanted into 100 ml fresh Musashige and Skoog liquid medium supplemented with 1.0 mg/l 2,4-dichlorophenoxyacetic acid and incubated at 25°C in the dark with rotary shaking at 120 rpm. In the complementary test (A2 + PSK), PSK was added into the medium at a final concentration of 100 nM. After 2 weeks of culture, fresh weights of cells were measured, and PSK-α and its analog concentrations in the CM were purified and quantified by LC/MS. Fresh weights are presented in gram and PSK concentrations as nanomolar. Averages of three independent experiments are given with the standard deviation. C1 is the transgenic cells harboring vector alone. A2, S2, and T1 are the transgenic cell lines harboring antisense, sense, or [Ser4]-mutated construct, respectively. UD, undetermined.