Fig. 1. Wounding induces activation of PLD. Corneal epithelial cells were seeded in the presence of agarose droplets (Block et al., 2004) and labeled with [³H]myristic acid. The agarose was removed and 1-butanol added for 5-minute intervals, and the amounts of radioactivity in phosphatidylbutanol (PtdBu) quantified (for details, see Materials and Methods). (A) Autoradiogram of thin-layer plates. (B) Time course of activation. The values in this and the following figures are means ± s.d. of triplicate determinations, except where noted. All experiments were performed at least three times with consistent results. (C) Effect of tyrphostin AG 1478 on PLD activation. Corneal epithelial cells were wounded and activities measured at 0-5 minutes with 10 µM UO126 or 10 µM tyrphostin AG 1478, as indicated. Control blots showed that the phosphorylation of the EGFR was completely blocked (data not shown, but see Fig. 7C,D).