Molecular cloning of ERp29, a novel and widely expressed resident of the endoplasmic reticulum
Molecular cloning of ERp29, a novel and widely expressed resident of the endoplasmic reticulum
复制标题
DOI：
10.1016/s0014-5793(96)01513-x
复制
发表时间：
1997-02-03
期刊：
影响因子：
3.5
通讯作者：
Hubbard, MJ
中科院分区：
文献类型：
--
作者：
Demmer, J;Zhou, CM;Hubbard, MJ
我们已经分离出一种新的29 kDa的蛋白质，在大鼠釉细胞中高度表达的全长cDNA克隆。该克隆编码一个259个残基的蛋白质，在此命名为ERp29，其结构特征（信号肽和一个变体内质网保留基序，KEEL）表明它是一种网状血浆蛋白。ERp29与蛋白质二硫键异构酶及其同源物具有有限的同源性，但缺乏其特征性的硫氧还蛋白样催化部分和钙结合基序。ERp29 mRNA表达在所有大鼠组织测试，并在其他动物的肝脏（灵长类动物，反刍动物，有袋动物）检测到同源转录。在人肝癌细胞中，ERp29 mRNA的表达并没有增加的应力（衣霉素，钙离子载体），诱导其他网状纤溶酶。我们的结论是，ERp29是一个新的，高度保守的成员，广泛表达的网状蛋白质家族。钙结合特性和应激反应的明显缺乏将ERp29与迄今为止表征的所有主要网状血浆蛋白区分开来。
We have isolated a full-length cDNA clone for a novel 29 kDa protein that is highly expressed in rat enamel cells. The clone encodes a 259-residue protein, here named ERp29, with structural features (signal peptide and a variant endoplasmic reticulum-retention motif, KEEL) that indicate it is a reticuloplasmin. ERp29 has limited homology with protein disulfide isomerase and its cognates, but lacks their characteristic thioredoxin-like catalytic moiety and calcium-binding motifs. ERp29 mRNA was expressed in all rat tissues tested, and a homologous transcript was detected in other animal livers (primate, ruminant, marsupial). In human hepatoma cells, ERp29 mRNA expression was not increased by stresses (tunicamycin, calcium ionophore) that induced other reticuloplasmins. We conclude that ERp29 is a new, highly conserved member of the reticuloplasmin family which is widely expressed. The apparent lack of both calcium binding properties and stress responsiveness distinguish ERp29 from all major reticuloplasmins characterised to date.