Role in Actin Cytoskeleton Rearrangements

The actin cytoskeleton is important in cell shape changes, polarization, motility, chemotaxis, metastasis and ceU division, and Rho family proteins play critical roles in these effects. The involvement of PLD in changes in the actin cytoskeleton was first suggested by the effects of exogenous PLD and PA, which induced actin stress fiber formation and also increased the F-actin content of fibroblasts [172, 173]. Another study utilizing endotheUal ceUs also showed that PA that was free of LPA induced actin stress fiber formation [174]. Furthermore, the effects of LPA to induce this change in the actin cytoskeleton and also PA formation were blocked by butan-l-ol, but not butan-2-ol [174] (Fig. 4.6). 

The association of PLD with the actin cytoskeleton is indicated by other studies [42, 178]. Thus / -actin has been shown to bind directly to PLDl and PLD2 [42]. Immunocytochemistry has also shown an association between both PLD isozymes with the actin cytoskeleton in intact cells. 

Texas red X-phalloidin. Addition of primary butanol (1-BuOH) inhibited stress fiber formation, whereas seconda butanol (2-BuOH) had no effect. 

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