Identification of an intestinal heme transporter
Identification of an intestinal heme transporter
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DOI：
10.1016/j.cell.2005.06.025
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发表时间：
2005-09-09
期刊：
影响因子：
64.5
通讯作者：
McKie, AT
中科院分区：
文献类型：
--
作者：
Shayeghi, M;Latunde-Dada, GO;McKie, AT
膳食血红素铁是食肉动物和杂食动物铁的重要营养来源，比来自蔬菜和谷物的非血红素铁更容易吸收。大部分血红素在近端肠道吸收，远端吸收能力降低。利用血红素吸收的肠道梯度，我们利用消减杂交方法从十二指肠分离血红素转运蛋白。在这里，我们展示了一种名为HCP 1（血红素载体蛋白1）的膜蛋白，与细菌金属四环素转运蛋白具有同源性，以温度依赖性和饱和的方式介导细胞对血红素的摄取。HCP 1 mRNA在十二指肠中高表达，并受缺氧调节。缺铁时，HCP 1蛋白受铁调节并定位于十二指肠肠细胞刷状缘膜。
Dietary heme iron is an important nutritional source of iron in carnivores and omnivores that is more readily absorbed than non-heme iron derived from vegetables and grain. Most heme is absorbed in the proximal intestine, with absorptive capacity decreasing distally. We utilized a subtractive hybridization approach to isolate a heme transporter from duodenum by taking advantage of the intestinal gradient for heme absorption. Here we show a membrane protein named HCP1 (heme carrier protein 1), with homology to bacterial metal-tetracycIine transporters, mediates heme uptake by cells in a temperature-dependent and saturable manner. HCP1 mRNA was highly expressed in duodenum and regulated by hypoxia. HCP1 protein was iron regulated and localized to the brush-border membrane of duodenal enterocytes in iron deficiency.