Heilmann C, Spamer C, Leberer E, Gerok W, Michalak M
Department of Gastroenterology, University of Freiburg, School of Medicine, Germany.
Biochem Biophys Res Commun. 1993 Jun 15;193(2):611-6. doi: 10.1006/bbrc.1993.1668.
A 60-kDa human calreticulin was isolated from liver homogenates. The protein was identified as calreticulin by its NH2-terminal amino acid sequence, by its mobility in SDS-PAGE, by its immunoreactivity with anti-calreticulin antibodies, by its Ca2+ binding, and by its localization to isolated ER membranes. In this study we show that Ca2+ binding to calreticulin results in Ca(2+)-dependent aggregation and precipitation of the protein. We also show that calreticulin and calsequestrin bind Zn2+ in 65Zn2+ overlay. In addition we have discovered that calreticulin exhibits a Zn(2+)-dependent interaction with hydrophobic matrix of phenyl-Sepharose that can be utilized in the purification of the protein.
从肝脏匀浆中分离出一种60 kDa的人钙网蛋白。通过其氨基末端氨基酸序列、在SDS-PAGE中的迁移率、与抗钙网蛋白抗体的免疫反应性、其Ca2+结合能力以及在分离的内质网（ER）膜上的定位，该蛋白质被鉴定为钙网蛋白。在本研究中，我们表明钙网蛋白与Ca2+结合会导致该蛋白质发生Ca(2+)依赖性聚集和沉淀。我们还表明，在65Zn2+覆盖实验中，钙网蛋白和肌浆网钙结合蛋白能结合Zn2+。此外，我们发现钙网蛋白与苯基琼脂糖的疏水基质存在Zn(2+)依赖性相互作用，可用于该蛋白质的纯化。
