Vogel L K, Suske G, Beato M, Norén O, Sjöström H
Department of Medical Biochemistry and Genetics, University of Copenhagen, Denmark.
FEBS Lett. 1993 Sep 20;330(3):293-6. doi: 10.1016/0014-5793(93)80891-w.
A complete cDNA encoding rabbit uteroglobin was constructed and expressed in MDCK and Caco-2 cells. The MDCK cells secrete uteroglobin in approximately equal amounts to the apical and the basolateral side, whereas the Caco-2 cells secrete uteroglobin mainly to the basolateral side. Both MDCK and Caco-2 cells thus secrete uteroglobin in a non-sorted manner. It has, however, previously been shown that uteroglobin is secreted exclusively at the apical membrane in primary cell culture of endometrial epithelial cells [S.K. Mani et al. (1991) Endocrinology 128, 1563-1573]. This suggests that either the endometrial epithelium has an apical default pathway or recognises a sorting signal not recognised by MDCK cells and Caco-2 cells. Our data thus show that a soluble molecule can be secreted at the apical, the basolateral or both membranes depending on the cell type.
构建了编码兔子宫珠蛋白的完整cDNA，并在MDCK细胞和Caco - 2细胞中进行表达。MDCK细胞向顶端和基底外侧分泌大致等量的子宫珠蛋白，而Caco - 2细胞主要向基底外侧分泌子宫珠蛋白。因此，MDCK细胞和Caco - 2细胞均以非分选的方式分泌子宫珠蛋白。然而，先前已经表明，在子宫内膜上皮细胞的原代细胞培养中，子宫珠蛋白仅在顶端膜分泌[S.K.马尼等人（1991年）《内分泌学》128卷，第1563 - 1573页]。这表明要么子宫内膜上皮细胞具有顶端默认途径，要么识别了MDCK细胞和Caco - 2细胞未识别的分选信号。因此，我们的数据表明，一种可溶性分子可以根据细胞类型在顶端膜、基底外侧膜或两者分泌。
