IDENTIFICATION OF HYPOCALCIN (TELEOCALCIN) ISOLATED FROM TROUT STANNIUS CORPUSCLES
IDENTIFICATION OF HYPOCALCIN (TELEOCALCIN) ISOLATED FROM TROUT STANNIUS CORPUSCLES
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DOI：
10.1016/0016-6480(88)90048-2
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发表时间：
1988-01-01
影响因子：
2.7
通讯作者：
BONGA, SEW
中科院分区：
文献类型：
--
作者：
LAFEBER, FPJG;HANSSEN, RGJM;BONGA, SEW
我们从鳟鱼的斯坦尼氏小体（CS）中分离纯化了一种糖蛋白，我们认为它是鱼类主要的低钙激素。该产物以相对大量存在于几种物质的CS中（即，欧洲鳗鱼、罗非鱼、金鱼和鲤鱼）。低钙蛋白通常响应于实验诱导的血钙浓度增加而从CS释放。超微结构观察表明，在这种处理后，1型细胞，据报道是CS的低钙素产生细胞类型，几乎完全脱颗粒。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳测定，分离的糖蛋白的表观分子量为54 kDa。该分子似乎易于分解，并在伴刀豆球蛋白-A亲和层析后作为41 kDa产物回收。使用还原剂如巯基乙醇或二硫苏糖醇，例如，在标准电泳技术期间或在氨基酸序列分析期间，仅允许回收28或18 kDa产物。有证据表明，54和41 kDa的产品是二聚体分子，与28和18 kDa的产品作为其各自的单体成分。这些产品的前33个N-末端氨基酸的序列和糖组分的组成。
We have isolated and purified a glycoprotein from the corpuscles of Stannius (CS) of trout, which we considered hypocalcin (also called teleocalcin), the major hypocalcemic hormone of fish. This product is present in relatively large amounts in the CS of several species (i.e., European eel, tilapia, goldfish, and carp). Hypocalcin is typically released from the CS in response to an experimentally induced increase of the blood calcium concentration. Ultrastructural observations show that after this treatment the type 1 cells, reportedly the hypocalcin-producing cell type of the CS, are almost completely degranulated. The isolated glycoprotein has an apparent molecular weight of 54 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This molecule appears susceptible to breakdown and is recovered upon concanavalin-A affinity chromatography as a 41 kDa product. Reducing agents such as mercaptoethanol or dithiothreitol employed, e.g., during standard electrophoretic techniques or during amino acid sequence analysis, allow only the recovery of 28 or 18 kDa products. Evidence is given that the 54 and 41 kDa products are dimer molecules, with the 28 and 18 kDa products as their respective monomeric constituents. The sequence of the first 33 N-terminal amino acids of these products and the composition of the sugar component are presented.