Retention of the transforming growth factor-beta 1 precursor in the Golgi complex in a latent endoglycosidase H-sensitive form.
Retention of the transforming growth factor-beta 1 precursor in the Golgi complex in a latent endoglycosidase H-sensitive form.
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转化生长因子-β1 前体以潜在的糖苷内切酶 H 敏感形式保留在高尔基复合体中。
DOI：
10.1016/s0021-9258(18)42818-9
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Carl
中科院分区：
文献类型：
--
作者：
Kohei MiyazonoSO;Johan ThybergflII;Carl
转化生长因子-β 1 (TGF-β 1) 在用佛波醇 12-肉豆蔻酸酯 13-乙酸酯处理的人红白血病细胞系 HEL 中合成为潜在的高分子量复合物。该复合物由三个成分组成：成熟 TGF-β 1、TGF-β 1 潜伏相关肽 (β 1-LAP) 和潜伏 TGF-β 1 结合蛋白 (LTBP)。 LTBP 在潜在 TGF-β 1 复合物的组装和分泌中发挥着重要作用；如果 TGF-β 1 前体无法与 LTBP 结合，则其大部分保留在细胞内，并且可能在 β 1-LAP 和成熟 TGF-β 1 分子之间含有异常二硫键（Miyazono, K.、Olofsson, A.、Colosetti, P. 和 Heldin, C.-H. (1991) EMBO J. 10, 1091-1101）。在目前的工作中，我们研究了细胞内保留的 TGF-β1 前体的亚细胞定位和特性。当 HEL 细胞被代谢标记并追踪长达 72 小时时，相当一部分 TGF-β 1 前体仍然以未处理的形式在细胞内观察到。 TGF-β 1 前体的分泌形式对糖苷内切酶 H 具有抗性，而 TGF-β 1 前体的细胞内形式对糖苷内切酶 H 敏感，无论是否存在甘露糖苷酶 II 抑制剂八氢吲嗪二醇。间接免疫荧光显微镜显示，TGF-β1 前体与甘露糖苷酶 II（高尔基复合体的标记物）共定位，但不与蛋白质二硫键异构酶（内质网的标记物）共定位。细胞内 TGF-β 1 前体由佛波醇 12-肉豆蔻酸酯 13-乙酸酯处理的 HEL 细胞制备，并测试 TGF-β 1 生物活性。在酸处理的 TGF-β 1 前体浓度为 80 pM 时，观察到水貂肺上皮细胞 Mv1Lu 的 DNA 合成的半最大抑制，而未经处理的材料显示出最小的生长抑制活性。综上所述，这些结果表明 TGF-β1 前体主要以潜在的、未成熟的形式保留在高尔基复合体的细胞内。
Transforming growth factor-beta 1 (TGF-beta 1) is synthesized as a latent high molecular weight complex in a human erythroleukemia cell line, HEL, treated with phorbol 12-myristate 13-acetate. The complex is comprised of three components: mature TGF-beta 1, the TGF-beta 1 latency-associated peptide (beta 1-LAP), and the latent TGF-beta 1-binding protein (LTBP). LTBP plays an important role in the assembly and secretion of the latent TGF-beta 1 complex; if the TGF-beta 1 precursor fails to bind to LTBP, much of it remains inside the cells and may contain anomalous disulfide bond(s) between beta 1-LAP and the mature TGF-beta 1 molecule (Miyazono, K., Olofsson, A., Colosetti, P., and Heldin, C.-H. (1991) EMBO J. 10, 1091-1101). In the present work, we have investigated the subcellular localization and properties of the TGF-beta 1 precursor retained intracellularly. When the HEL cells were metabolically labeled and chased for up to 72 h, a considerable part of the TGF-beta 1 precursor was still observed intracellularly in an unprocessed form. The secreted form of the TGF-beta 1 precursor was resistant to endoglycosidase H, whereas the intracellular form of the TGF-beta 1 precursor was sensitive to endoglycosidase H, regardless of the presence or absence of swainsonine, an inhibitor of mannosidase II. Indirect immunofluorescence microscopy revealed that the TGF-beta 1 precursor co-localized with mannosidase II, a marker for the Golgi complex, but not with protein disulfide isomerase, a marker for the endoplasmic reticulum. The intracellular TGF-beta 1 precursor was prepared from phorbol 12-myristate 13-acetate-treated HEL cells and tested for TGF-beta 1 bioactivity. Half-maximal inhibition of the DNA synthesis in mink lung epithelial cells, Mv1Lu, was observed at 80 pM of the acid-treated TGF-beta 1 precursor, whereas nontreated material showed minimal growth inhibitory activity. Taken together, these results indicate that the TGF-beta 1 precursor is retained inside the cells in the Golgi complex, mainly in a latent, immature form.