A study of the protein secretory pathway of Aspergillus niger using a glucoamylase-GFP fusion protein
A study of the protein secretory pathway of Aspergillus niger using a glucoamylase-GFP fusion protein
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DOI：
10.1006/fgbi.2000.1245
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发表时间：
2001-02-01
影响因子：
3
通讯作者：
Robson, GD
中科院分区：
文献类型：
--
作者：
Khalaj, V;Bookman, JL;Robson, GD
使用表达葡糖淀粉酶-GFP融合蛋白的菌株在尼日尔曲霉中观察阻断蛋白分泌的各种处理的效果。冷休克引起的保留在网状网络（ER）的融合蛋白与明亮的节点，可能代表高尔基体。用布雷菲德菌素A（BFA）处理胚苗最初也引起ER内的积累，但长时间暴露导致融合蛋白形成并靶向ER的空泡。破坏肌动蛋白与细胞松弛素A最初导致微弱的弥漫性积累，并最终形成的聚集体，这不是空泡，表明肌动蛋白细胞骨架是重要的分泌囊泡运输。用诺考达唑破坏微管导致超支化，但不引起细胞内积累，这表明微管在指导囊泡运输而不是囊泡运动本身中发挥作用。再生原生质体的处理证实，BFA和细胞松弛素，但不是诺考达唑抑制蛋白质分泌。当幼苗进行碳饥饿，空泡迅速启动整个菌丝和GFP荧光可见的一些液泡，表明重新定位的融合蛋白从分泌途径的液泡。
The effect of various treatments that block protein secretion was visualized in Aspergillus niger using a strain expressing a glucoamylase-GFP fusion protein. Cold shock caused the retention of the fusion protein in a reticulate network (ER) with brighter nodes that may represent Golgi bodies. Treatment of germlings with brefeldin A (BFA) also initially caused accumulation within the ER but prolonged exposure led to the formation and targeting of the fusion protein to vacuoles from the ER. Disruption of actin with cytochalasin A initially led to a faint diffuse accumulation and ultimately to the formation of aggregated bodies which were not vacuoles, suggesting that the actin cytoskeleton is important in secretary vesicle transport. Disruption of microtubules with nocodazole led to hyperbranching but did not cause intracellular accumulation, suggesting that microtubules play a Pole in directing vesicle transport rather than vesicle movement per se. Treatment of regenerating protoplasts confirmed that BFA and cytochalasin but not nocodazole inhibited protein secretion. When germlings were subjected to carbon starvation, vacuolation was rapidly initiated throughout the hyphae and GFP fluorescence was visible in some of the vacuoles, indicating retargeting of the fusion protein from the secretory pathway to the vacuoles.