Indirect immunofluorescence localization of ponticulin in motile cells.
Indirect immunofluorescence localization of ponticulin in motile cells.
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运动细胞中脑桥蛋白的间接免疫荧光定位。
DOI：
10.1002/cm.970130404
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发表时间：
1989
影响因子：
--
通讯作者：
Luna,EJ
中科院分区：
文献类型：
--
作者：
Wuestehube,LJ;Chia,CP;Luna,EJ
脑桥蛋白是从对数生长期盘状网柄藻中分离的质膜中主要的肌动蛋白结合整合糖蛋白。因此，该蛋白质似乎是质膜和肌动蛋白丝之间的重要连接（Wuestehube和Luna：Journal of Cell Biology 105：1741-1751，1987）。本研究采用间接免疫荧光显微镜技术，观察了随机移动的D.盘状阿米巴和阿米巴中参与细胞迁移和吞噬作用。脑桥蛋白分布在整个质膜中，也存在于与细胞核附近的微管组织中心-高尔基复合体相关的细胞内囊泡中。在聚集性阿米巴中，桥脑蛋白集中在细胞-细胞横向接触区域和质膜的拱形区域。脑桥蛋白也存在于丝状伪足、极化细胞富含肌动蛋白的前端和洗涤剂不溶性细胞骨架中，但不明显富集。在参与酵母吞噬作用的阿米巴中，存在脑桥蛋白，但在吞噬杯中不富集，并且与吞噬酵母周围的胞内囊泡相关。这些结果表明，桥脑蛋白在质膜的某些区域与肌动蛋白丝稳定结合，桥脑蛋白的肌动蛋白结合活性可能受到严格控制。间接免疫荧光显微镜和免疫印迹分析表明，人多形核白细胞也含有一种17 kD的蛋白质，该蛋白质与抗D亲和纯化抗体特异性交叉反应。盘状脑桥蛋白与盘状杜氏酵母一样，哺乳动物17 kD脑桥蛋白类似物似乎定位于质膜，在富含肌动蛋白的细胞延伸中很明显。这些结果表明，桥脑蛋白介导的质膜和肌动蛋白之间的连接可能存在于高等真核细胞中。
Ponticulin is the major actin‐binding integral glycoprotein in plasma membranes isolated from log‐phaseDictyostelium discoideumamebae. As such, this protein appears to be an important link between the plasma membrane and actin filaments (Wuestehube and Luna:Journal of Cell Biology105:1741–1751, 1987). In this study, indirect immunofluorescence microcopy was used to examine the distribution of ponticulin in randomly movingD. discoideumamebae and in amebae engaged in cell migration and phagocytosis. Ponticulin is distributed throughout the plasma membrane and also is present in intracellular vesicles associated with the microtubule‐organizing center‐Golgi complex adjacent to the nucleus. In aggreating amebae, ponticulin is concentrated in regions of lateral cell‐cell contact and in arched regions of the plasma membrane. Ponticulin also is present, but not obviously enriched, in filopodia, in the actin‐rich anterior end of polarized cells, and in detergent‐insoluble cytoskeletons. In amebae engaged in phagocytosis of yeast, ponticulin is present but not enriched in phagocytic cups and is associated with intracellular vesicles around engulfed yeast. These results suggest that ponticulin is stably associated with actin filaments in certain regions of the plasma membrace and that the actin‐binding activity of ponticulin may be tightly controlled.Indirect immupofluorescence microscopy and immunoblot analysis demonstrate that human polymorphonuclear leukocytes also contain a 17 kD protein that specifically cross‐reacts with antibodies affinity‐purified aganstD. discoideumponticulin. As inD. discoideum, the mammalian 17 kD ponticulin‐analog appears to be localized in plasma membrane and is evident in actin‐rich cell extensions. These results indicate that ponticulin‐mediated linkages between the plasma membrane and actin may be present in higher eukaryotic cells.