MESOSECRIN - A SECRETED GLYCOPROTEIN PRODUCED IN ABUNDANCE BY HUMAN MESOTHELIAL, ENDOTHELIAL, AND KIDNEY EPITHELIAL-CELLS IN CULTURE
MESOSECRIN - A SECRETED GLYCOPROTEIN PRODUCED IN ABUNDANCE BY HUMAN MESOTHELIAL, ENDOTHELIAL, AND KIDNEY EPITHELIAL-CELLS IN CULTURE
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DOI：
10.1083/jcb.104.2.263
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发表时间：
1987-02-01
影响因子：
7.8
通讯作者：
PLUMMER, KK
中科院分区：
文献类型：
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作者：
RHEINWALD, JG;JORGENSEN, JL;PLUMMER, KK
培养中生长的人间皮细胞、内皮细胞和II型肾上皮细胞3%的总蛋白质合成的生产。46-kD，pI 7.1，分泌糖蛋白（指定为Sp 46）。成纤维细胞产生的Sp 46约为这些细胞类型的十分之一，它们的合成依赖于氢化可的松。角化细胞、尿路上皮细胞、结膜上皮细胞和乳腺上皮细胞不产生可检测量的Sp 46。间皮细胞将Sp 46分泌到基质上，随后从那里将其释放到培养基中。使用特异性抗血清的免疫荧光分析揭示了Sp 46作为基质上的精细涂层沉积在细胞下方。在稀疏培养物中，在运动细胞后面的踪迹中检测到Sp 46。相比之下，分泌的纤连蛋白聚结成纤维，其中大部分保持与细胞接触并在细胞顶部;因此Sp 46不优先结合纤连蛋白。人Sp 46的质量中约6 kD是N-连接的寡糖，其在分泌前被末端唾液酸化。Sp 46具有低甘氨酸含量，表明其不是胶原样蛋白。它的前40个氨基酸的NH 2-末端序列与任何可获得序列信息的蛋白质都不相似。Sp 46似乎是一种新的细胞外糖蛋白，其高水平的组成性表达仅限于中胚层来源的上皮细胞和内皮细胞。因此我们建议将其命名为“中分泌素”。
Human mesothelial cells, endothelial cells, and type II kidney epithelial cells growing in culture devote .apprx. 3% of their total protein synthesis to the production of an Mr .apprx. 46-kD, pI 7.1, secreted glycoprotein (designated Sp46). Fibroblasts make about 1/10th as much Sp46 as these cell types, and their synthesis is dependent upon hydrocortisone. Keratinocytes, urothelial cells, conjunctival epithelial cells, and mammary epithelial cells do not make detectable amounts of Sp46. Mesothelial cells secrete Sp46 onto the substratum, and from there it is subsequently released into the medium. Immunofluorescence analysis using specific antisera discloses that Sp46 is deposited beneath cells as a fine coating on the substratum. In sparse cultures, Sp46 is detected in trails behind motile cells. In contrast, secreted fibronectin coalesces into fibers, most of which remain in contact with and on top of the cells; thus Sp46 does not preferentially bind to fibronectin. About 6 kD of the mass of human Sp46 is N-linked oligosaccharide, which is terminally sialated before secretion. Sp46 has a low glycine content, indicating that it is not a collagenlike protein. Its NH2-terminal sequence over the first 40 amino acids does not resemble any protein for which sequence information is available. Sp46 appears to be a novel extracellular glycoprotein, high-level constitutive expression of which is restricted to mesoderm-derived epithelial and endothelial cells. We therefore propose for it the name ''''mesosecrin''''.