Ludowyke R I, Kawasugi K, French P W
Centre for Immunology, St. Vincent's Hospital, Sydney, Australia.
Eur J Cell Biol. 1994 Aug;64(2):357-67.
Rat basophilic leukemia cells (RBL-2H3) undergo morphological and cytoskeletal changes during antigen (DNP-BSA) or calcium ionophore-induced secretion of allergic mediators from intact or permeabilized cells. We describe the novel finding that the phosphatase-resistant ATP analogue, ATP gamma S, mimics antigen-induced serotonin secretion and cytoskeletal rearrangements in permeabilized cells. Confocal microscopy of unstimulated cells shows that myosin and F-actin are concentrated at the plasma membrane. Upon addition of ATP gamma S, F-actin becomes rearranged into membrane ruffles and also associates with myosin in a cytoplasmic meshwork, concentrated perinuclearly. F-actin and myosin ultimately become colocalized into parallel microfilament bundles located on the basolateral membrane. During this period the cell height decreases whilst the cell area increases more than twofold. Gel electrophoresis shows that the cytoskeletal proportion of actin remains unchanged, indicating that the rearrangements occur within the total F-actin pool. The distribution of microtubules and intermediate filaments is unchanged in the presence of ATP gamma S. These results suggest that overcoming a phosphatase may be sufficient to induce secretion in RBL-2H3 cells, and that this secretion may be regulated by F-actin and myosin rearrangements.
大鼠嗜碱性白血病细胞（RBL - 2H3）在抗原（二硝基苯基牛血清白蛋白，DNP - BSA）或钙离子载体诱导完整或通透细胞分泌过敏介质的过程中，会发生形态和细胞骨架的变化。我们描述了一个新发现，即抗磷酸酶的ATP类似物ATPγS在通透细胞中模拟抗原诱导的5 - 羟色胺分泌和细胞骨架重排。未刺激细胞的共聚焦显微镜观察显示，肌球蛋白和F - 肌动蛋白集中在质膜上。加入ATPγS后，F - 肌动蛋白重排形成膜褶，并在细胞质网络中与肌球蛋白结合，集中在核周。F - 肌动蛋白和肌球蛋白最终共定位到位于基底外侧膜上的平行微丝束中。在此期间，细胞高度降低，而细胞面积增加两倍以上。凝胶电泳显示肌动蛋白的细胞骨架比例保持不变，表明重排在总F - 肌动蛋白池中发生。在ATPγS存在的情况下，微管和中间丝的分布没有变化。这些结果表明，克服磷酸酶可能足以诱导RBL - 2H3细胞分泌，并且这种分泌可能受F - 肌动蛋白和肌球蛋白重排的调节。
