Involvement of dynamin-2 in formation of discoid vesicles in urinary bladder umbrella cells.
Involvement of dynamin-2 in formation of discoid vesicles in urinary bladder umbrella cells.
复制标题
dynamin-2 参与膀胱伞细胞盘状囊泡的形成。
DOI：
10.1007/s00441-009-0804-z
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发表时间：
2009
影响因子：
3.6
通讯作者：
Ohno,Shinichi
中科院分区：
文献类型：
--
作者：
Terada,Nobuo;Ohno,Nobuhiko;Saitoh,Sei;Saitoh,Yurika;Fujii,Yasuhisa;Kondo,Tetsuo;Katoh,Ryohei;Chan,Cheryl;Abraham,SomanN;Ohno,Shinichi
膀胱上皮伞状细胞(UC)通过调节细胞内盘状小泡(DV)的胞吐/内吞作用来控制膀胱容量。动力蛋白(Dyn)是一种GTP酶，通过细胞膜的断裂促进内吞过程。我们研究了Dy2，最丰富的dyn形式，是否在UC中表达，并对其内吞作用做出贡献。用抗Dy2的特异性抗体通过免疫组织化学方法在人和啮齿动物的UCs中定位Dy2。为了阐明DYN-GTP酶抑制剂DYN-GTP酶抑制剂DYNORE对小鼠膀胱的作用，研究了DYN-GTP酶抑制剂对小鼠膀胱UC结构的影响。由于尿路致病性大肠埃希氏菌可以在感染过程中被包裹到UC中，我们使用免疫组织化学方法来确定感染UC中的包裹细菌的部分是否也富含Dy2。光镜下可见Dy2在UC中大量表达，尤其是在顶端胞浆附近。免疫电子显微镜观察发现，在UC的DV膜上及其周围可见Dy2。用快速冷冻和深度蚀刻方法进行的超微结构分析证实了这些发现，并揭示了与DV膜密切相关的明显的Dy2结合微丝的存在。Dyasore治疗可显著减少UCs中DV的数量。在受感染的UC中，大肠杆菌被包裹在富含Dy2的隔间中。因此，Dy2在UCs中高度富含，主要与UCs中的DV膜和微丝有关。用王朝抑制剂预处理膀胱。UC的结肠侵袭。因此，Dy2有助于DV的结构完整性和UC的内吞活性。
Umbrella cells (UCs) of the epithelium of the urinary bladder have the capacity to control bladder volume by regulating exocytosis/endocytosis of their intracellular discoid vesicles (DVs). Dynamin (Dyn) is a GTPase that promotes endocytic processes through scission of cell membranes. We have examined whether Dyn2, the most abundant Dyn form, is expressed in UCs and contributes to their endocytic actions. A specific antibody against Dyn2 was used to localize Dyn2 in human and rodent UCs by immunohistochemistry. To clarify the functional roles of Dyn2, mouse bladders were treated with a Dyn-GTPase inhibitor, dynasore, and its effects on their UC structure were assessed. Since uropathogenicEscherichia colican be encased into UCs during infection, we used immunohistochemistry to determine whether bacteria-encasing compartments in the infected UCs were also enriched with Dyn2. Light microscopy showed that Dyn2 was abundantly expressed in UCs, especially near the apical cytoplasmic regions. By immunoelectron microscopy, Dyn2 was found on and around DV membranes in UCs. Ultrastructural analysis with a quick-freezing and deep-etching method confirmed these findings and revealed the existence of distinct Dyn2-bound microfilaments in close association with DV membranes. Dynasore treatment of bladders markedly reduced the number of DVs in UCs. In infected UCs,E. coliwas encased in compartments enriched in Dyn2. Therefore, Dyn2 is highly enriched in UCs and mostly associated with membranes of DVs and microfilaments in the UCs. Pretreatment of bladders with dynasore inhibitsE. coliinvasion of UCs. Dyn2 thus contributes to the structural integrity of DVs and to the endocytic activity of UCs.