Department of Cell Biology, Heidelberg Institute for Plant Sciences, University of Heidelberg, D-69120 Heidelberg, Germany.
J Exp Bot. 2011 May;62(8):2949-57. doi: 10.1093/jxb/err007. Epub 2011 Feb 28.
The effects of two brefeldin A (BFA) analogues (BFA lactam; 6(R)-hydroxy-BFA) on plant cells were tested. Although these two compounds elicited BFA-like effects in mammalian cells, the lactam analogue failed to elicit a response in plant cells. By contrast, while the 6(R)-hydroxy-BFA analogue gave rise to a classic BFA response in tobacco mesophyll protoplasts and true leaves of Arabidopsis (redistribution of Golgi enzymes into the ER), it failed to cause the formation of BFA-compartments in Arabidopsis root cells and cotyledonary leaves. Even when the GNL1-LM mutant of Arabidopsis, which has a cis-Golgi located BFA-sensitive ARF-GEF, was used, the 6(R)-hydroxy analogue failed to elicit a response at conventional BFA concentrations. Only at concentrations of over 200 μM did 6(R)-hydroxy-BFA elicit a BFA-like effect. These differences are interpreted in terms of the different properties of the respective TGN- (Arabidopsis roots) and cis-Golgi- (tobacco mesophyll) localized BFA-sensitive ARF-GEFs.
测试了两种布雷菲德菌素 A (BFA)类似物（BFA 内酰胺；6(R)-羟基-BFA）对植物细胞的影响。尽管这两种化合物在哺乳动物细胞中引起了类似于 BFA 的效应，但内酰胺类似物未能在植物细胞中引起反应。相比之下，虽然 6(R)-羟基-BFA 类似物在烟草叶肉原生质体和拟南芥的真叶中引起了典型的 BFA 反应（高尔基体酶重新分布到内质网），但它未能导致拟南芥根细胞和子叶中形成 BFA 区室。即使使用具有位于顺式高尔基体的 BFA 敏感 ARF-GEF 的拟南芥 GNL1-LM 突变体，在常规 BFA 浓度下，6(R)-羟基类似物也未能引起反应。只有在浓度超过 200 μM 时，6(R)-羟基-BFA 才会引起类似于 BFA 的效应。这些差异可以根据各自的 TGN-（拟南芥根）和顺式高尔基体-（烟草叶肉）定位的 BFA 敏感 ARF-GEF 的不同特性来解释。
