Colocalization of ferroportin-1 with hephaestin on the basolateral membrane of human intestinal absorptive cells
Colocalization of ferroportin-1 with hephaestin on the basolateral membrane of human intestinal absorptive cells
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DOI：
10.1002/jcb.21392
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发表时间：
2007-07-01
影响因子：
4
通讯作者：
Kim, Eun-Young
中科院分区：
文献类型：
--
作者：
Han, Okhee;Kim, Eun-Young
铁转运蛋白-1（FPN-1）和多铜氧化酶hephaestin（Heph）被预测在肠细胞的基底外侧膜上表达，并参与铁转运穿过肠细胞基底外侧膜的过程。然而，目前尚不清楚这些蛋白质在肠吸收细胞中的确切位置。我们使用完全分化的Caco-2细胞检测了FPN-1和Heph在肠吸收细胞中的细胞定位。共聚焦显微镜研究表明，FPN-1和Heph位于基底外侧膜上，它们与在微孔膜插入物上生长的完全分化的Caco-2细胞中的转铁蛋白受体（TfR）相关。而在隐窝细胞样增殖的Caco-2细胞中未检测到Heph蛋白。在稳定转染的人肠吸收细胞中，通过在C端添加GFP修饰人FPN-1，我们发现FPN-1-GFP位于基底外侧膜上，并且与Heph相关，这表明FPN-1可能在铁穿过肠吸收细胞基底外侧膜的过程中与Heph相关并相互作用。
An iron exporter ferroportin-1 (FPN-1) and a multi-copper oxidase hephaestin (Heph) are predicted to be expressed on the basolateral membrane of the enterocyte and involved in the processes of iron export across the basolateral membrane of the enterocyte. However, it is not clear where these proteins are exactly located in the intestinal absorptive cell. We examined cellular localization of FPN-1 and Heph in the intestinal absorptive cells using the fully differentiated Caco-2 cells. Confocal microscope study showed that FPN-1 and Heph are located on the basolateral membrane and they are associated with the transferrin receptor (TfR) in fully differentiated Caco-2 cells grown on microporous membrane inserts. However, Heph protein was not detected in the crypt cell-like proliferating Caco-2 cell. In stably transfected human intestinal absorptive cells expressing human FPN-1 modified by the addition of GFP at the C-terminus, we show that FPN-1-GFP is located on the basolateral membrane and it is associated with Heph suggesting the possibility that FPN-1 might associate and interact with Heph in the process of iron exit across the basolateral membrane of intestinal absorptive cell.