XVI International Botanical Congess
In the green alga Scenedesmus, Golgi bodies are situated close to the nuclear envelope, and receive the transition vesicles not directly from the ER but from the nuclear envelope. Brefeldin A (BFA) induced a redistribution of Golgi membrane and its marker enzyme (thiamine pyrophosphatase) into the ER via the nuclear envelope by inhibiting anterograde transport (Noguchi et al. 1998). The cytoskeleton involved in this BFA-induced retrograde pathway was investigated with an electron microscopy. Both oryzalin (microtubule-disrupting agent) and cytochalasin B inhibited this retrograde pathway. Yet in non-treated cells, only actin filaments were observed between the nuclear envelope and Golgi bodies. The results suggest that the retrograde transport is actin filament dependent in non-treated cells.