洋葱鳞茎表皮Actin细胞骨架的Rh—Ph荧光和光学显微镜观察

洋葱鳞茎内表皮细胞经Triton X-100处理和多聚甲醛固定之后用Rh-Ph(Rhodamine-Phalloidin)染色,细胞质内可见较丰富的、直径为100—300nm的F-actin束。较粗的F-actin束沿细胞的长轴平行排列,并纵裂成较细的“分枝”,纵裂成的分枝又纵裂成更细的“分枝”。各种大小的F-actin束相互交织在一起构成一个三维的纤丝网络,并且与细胞膜、细胞核和其它细胞器相连。经同样方法处理和固定的细胞用考马斯亮兰R_(250)(Coomassie brilliant blue R_(250))染色之后,细胞质内可见直径为200—300nm的纤丝,形态特征和排列方式和上述在荧光显微镜下看到的F-actin束相同。本研究结果表明洋葱鳞茎内表皮的细胞骨架包含较丰富的F-actin系统;Pena的考马斯亮兰染色法(1980)所显示的结构主要代表F-actin束。

THE RH-PH FLUORESCENCE AND LIGHT MICROSCOPE OBSERVATION OF THE ACTIN CYTOSKELETON IN ONION BULB EPIDERMIS CELLS

After the inner epidermis of bulb scales of onion (Allium cepa) was incubated in Triton X-100, fixed with paraformaldehyde and then stained with Rh-Ph (rhodamine-phalloidin) , many F-actin bundles(cables), which were 100-300 nm thick, became visible. The somewhat thick F-actin bundles were arranged in a parallel direction with the longitudinal axis of a cell and could fray into 2-3 thinner branches, which could further do the same. The F-actin bundies of various thickness were interlaced into a three dimensional fibrillar network and associated with nucleus, plasma membrane and other organelles. After the cells,having undergone the same pretreatment and fixation,were stained with Coomassie brilliant blue R_(250), many fibrillar structures 200-300 nm thick could be seen, which were similar in morphology and arrangement pattern to the F-actin bundies visualized by Rh-Ph staining. This result suggests that the cytoskeleton of onion bulb epidermis contains richer F-actin bundles and that the fibrillar structure visualized with Pena's Coomassie blue staining is mainly F-actin bundles.