Birbeck granules are subdomains of endosomal recycling compartment in human epidermal Langerhans cells, which form where langerin accumulates
Birbeck granules are subdomains of endosomal recycling compartment in human epidermal Langerhans cells, which form where langerin accumulates
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DOI：
10.1091/mbc.01-06-0300
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发表时间：
2002-01-01
影响因子：
3.3
通讯作者：
Hanau, D
中科院分区：
文献类型：
--
作者：
Mc Dermott, R;Ziylan, U;Hanau, D
Birbeck颗粒是表皮朗格汉斯细胞特有的不寻常的杆状结构，其起源和功能尚未确定。我们研究了细胞内的位置和命运的Langerin，一种蛋白质牵连在Birbeck颗粒的生物发生，在人表皮朗格汉斯细胞。在稳态下，Langerin主要存在于内体再循环隔室和Birbeck颗粒中。Langerin通过经典的受体介导的内吞作用内化，并且内吞的Langerin可接近的第一个Birbeck颗粒是与Langerin积累的中心粒周围区域中的再循环内体连接的颗粒。药物诱导的内吞抑制导致大量的开放式Birbeck颗粒样结构的外观附加到质膜，而抑制回收诱导Birbeck颗粒合并与管状内体网络。在成熟的朗格汉斯细胞中，Langerin交通被废除，内部Langerin的损失与Birbeck颗粒的伴随消耗有关。我们的研究结果表明，早期的内体室和质膜之间的交换兰热蛋白，与动态保留在内体再循环隔室。他们表明，Birbeck颗粒不是内吞结构，而是内体再循环隔室的子域，在Langerin积累的地方形成。最后，我们的研究结果牵连ADP-核糖基化因子蛋白在郎格林运输和Birbeck颗粒和其他内体膜之间的交换。
Birbeck granules are unusual rod-shaped structures specific to epidermal Langerhans cells, whose origin and function remain undetermined. We investigated the intracellular location and fate of Langerin, a protein implicated in Birbeck granule biogenesis, in human epidermal Langerhans cells. In the steady state, Langerin is predominantly found in the endosomal recycling compartment and in Birbeck granules. Langerin internalizes by classical receptor-mediated endocytosis and the first Birbeck granules accessible to endocytosed Langerin are those connected to recycling endosomes in the pericentriolar area, where Langerin accumulates. Drug-induced inhibition of endocytosis results in the appearance of abundant open-ended Birbeck granule-like structures appended to the plasma membrane, whereas inhibition of recycling induces Birbeck granules to merge with a tubular endosomal network. In mature Langerhans cells, Langerin traffic is abolished and the loss of internal Langerin is associated with a concomitant depletion of Birbeck granules. Our results demonstrate an exchange of Langerin between early endosomal compartments and the plasma membrane, with dynamic retention in the endosomal recycling compartment. They show that Birbeck granules are not endocytotic structures, rather they are subdomains of the endosomal recycling compartment that form where Langerin accumulates. Finally, our results implicate ADP-ribosylation factor proteins in Langerin trafficking and the exchange between Birbeck granules and other endosomal membranes.