Distinct subcellular localization of calcium binding S100 proteins in human smooth muscle cells and their relocation in response to rises in intracellular calcium.
Distinct subcellular localization of calcium binding S100 proteins in human smooth muscle cells and their relocation in response to rises in intracellular calcium.
复制标题
人平滑肌细胞中钙结合 S100 蛋白的独特亚细胞定位及其响应细胞内钙升高的重新定位。
作者：
A. Mandinova;D. Atar;B. Schäfer;M. Spiess;U. Aebi;C. Heizmann
细胞内Ca ~（2+）浓度的变化控制着广泛的细胞反应，而细胞内Ca ~（2+）结合蛋白是通过与不同类型的靶蛋白相互作用抑制Ca ~（2+）信号传导的关键分子。其中，S100钙离子结合蛋白，其特征在于一个共同的结构基序，EF-手，最近吸引了主要的兴趣，由于他们的细胞和组织特异性表达模式和参与各种病理过程。我们的研究的目的是确定S100蛋白的亚细胞定位在血管平滑肌细胞系来自人主动脉和肠平滑肌，并在原代细胞培养物来自动脉平滑肌组织在正常条件下和刺激后的细胞内Ca 2+浓度。共聚焦激光扫描显微镜与专门设计的共定位软件一起使用。观察到S100蛋白的独特细胞内定位：S100 A6存在于肌浆网以及细胞核中。S100 A1和S100 A4主要存在于细胞质中，在那里它们与肌浆网和肌动蛋白应力纤维密切相关。相反，S100 A2主要位于细胞核中。使用沉降试验和随后的负染色后的电子显微镜，我们证明，S100 A1直接与丝状肌动蛋白在Ca 2+依赖的方式相互作用。在毒胡萝卜素（1 μ M）诱导细胞内Ca ~（2+）浓度增加后，在细胞肌浆网区域形成了具有高S100蛋白含量的特异性囊泡结构。总之，我们证明了一个独特的亚细胞定位模式的S100蛋白和它们的相互作用与肌动蛋白丝和肌浆网在人平滑肌细胞。S100蛋白在细胞内Ca ~（2+）增加后的特异性转位支持了S100蛋白在平滑肌细胞Ca ~（2+）稳态调节中发挥几种重要功能的假设。
Changes in cytosolic Ca2+ concentration control a wide range of cellular responses, and intracellular Ca2+-binding proteins are the key molecules to transduce Ca2+ signaling via interactions with different types of target proteins. Among these, S100 Ca2+-binding proteins, characterized by a common structural motif, the EF-hand, have recently attracted major interest due to their cell- and tissue-specific expression pattern and involvement in various pathological processes. The aim of our study was to identify the subcellular localization of S100 proteins in vascular smooth muscle cell lines derived from human aorta and intestinal smooth muscles, and in primary cell cultures derived from arterial smooth muscle tissue under normal conditions and after stimulation of the intracellular Ca2+ concentration. Confocal laser scanning microscopy was used with a specially designed colocalization software. Distinct intracellular localization of S100 proteins was observed: S100A6 was present in the sarcoplasmic reticulum as well as in the cell nucleus. S100A1 and S100A4 were found predominantly in the cytosol where they were strongly associated with the sarcoplasmic reticulum and with actin stress fibers. In contrast, S100A2 was located primarily in the cell nucleus. Using a sedimentation assay and subsequent electron microscopy after negative staining, we demonstrated that S100A1 directly interacts with filamentous actin in a Ca2+-dependent manner. After thapsigargin (1 microM) induced increase of the intracellular Ca2+ concentration, specific vesicular structures in the sarcoplasmic reticulum region of the cell were formed with high S100 protein content. In conclusion, we demonstrated a distinct subcellular localization pattern of S100 proteins and their interaction with actin filaments and the sarcoplasmic reticulum in human smooth muscle cells. The specific translocation of S100 proteins after intracellular Ca2+ increase supports the hypothesis that S100 proteins exert several important functions in the regulation of Ca2+ homeostasis in smooth muscle cells.
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DOI：
10.1016/0167-4889(94)90101-5
发表时间：
1994-09
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
L. V. Van Eldik;W. Griffin
通讯作者：
L. V. Van Eldik;W. Griffin
S100A2 与肌肉和非肌肉原肌球蛋白的 Ca2 依赖性相互作用。
影响因子：
4
作者：
Gimona,M;Lando,Z;Dolginov,Y;Vandekerckhove,J;Kobayashi,R;Sobieszek,A;Helfman,DM
通讯作者：
Helfman,DM
DOI：
10.1073/pnas.89.6.2504
发表时间：
1992-03-15
影响因子：
11.1
作者：
LEE, SW;TOMASETTO, C;SAGER, R
通讯作者：
SAGER, R
S100A1/S100B 靶蛋白的鉴定：磷酸葡萄糖变位酶。
影响因子：
4
作者：
Landar,A;Caddell,G;Chessher,J;Zimmer,DB
通讯作者：
Zimmer,DB
DOI：
10.1016/s0021-9258(18)60647-7
发表时间：
1988-04
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
J. Baudier;R. Cole
通讯作者：
J. Baudier;R. Cole