Sequential exocytosis of insulin granules is associated with redistribution of SNAP25.
Sequential exocytosis of insulin granules is associated with redistribution of SNAP25.
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DOI：
10.1083/jcb.200312033
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发表时间：
2004-04-26
期刊：
影响因子：
--
通讯作者：
Kasai H
中科院分区：
文献类型：
--
作者：
Takahashi N;Hatakeyama H;Okado H;Miwa A;Kishimoto T;Kojima T;Abe T;Kasai H
我们使用极性荧光示踪剂磺酰罗丹明B和融合蛋白的双光子激发成像研究了完整胰岛β细胞中的顺序胞吐作用，所述融合蛋白包括用腺病毒载体转染的增强型青色荧光蛋白（ECFP）和SNARE蛋白SNAP 25（25 kD的突触体相关蛋白）。在各种条件下用葡萄糖刺激或通过笼状Ca 2+化合物的光解刺激的β细胞中，发现顺序胞吐占胞吐事件的<10%。多颗粒胞吐，其中颗粒与颗粒融合发生在胞吐之前，很少found. We检测到ECFP-SNAP 25从质膜到融合颗粒膜的再分配发生在大比例（54%）的连续胞吐事件，但只有一小部分（5%）的孤立融合事件。用甲基-β-环糊精去除细胞膜中的胆固醇，使ECFP-SNAP 25的再分布和顺序的胞吐增加了3倍。这些观察结果支持了SNAP 25是一种质膜因子的假设，该因子负责顺序胞吐。
We have investigated sequential exocytosis in β cells of intact pancreatic islets with the use of two-photon excitation imaging of a polar fluorescent tracer, sulforhodamine B, and a fusion protein comprising enhanced cyan fluorescent protein (ECFP) and the SNARE protein SNAP25 (synaptosome-associated protein of 25 kD) transfected with an adenoviral vector. Sequential exocytosis was found to account for <10% of exocytic events in β cells stimulated either with glucose under various conditions or by photolysis of a caged-Ca2+ compound. Multigranular exocytosis, in which granule-to-granule fusion occurs before exocytosis, was rarely found. We detected redistribution of ECFP-SNAP25 from the plasma membrane into the membrane of the fused granule occurred in a large proportion (54%) of sequential exocytic events but in only a small fraction (5%) of solitary fusion events. Removal of cholesterol in the plasma membrane by methyl-β-cyclodextrin facilitated both redistribution of ECFP-SNAP25 and sequential exocytosis by threefold. These observations support the hypothesis that SNAP25 is a plasma membrane factor that is responsible for sequential exocytosis.
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影响因子：
3.8
作者：
DETOLEDO, GA;FERNANDEZ, JM
通讯作者：
FERNANDEZ, JM
影响因子：
6.5
作者：
TAI, PC;SPRY, CJF
通讯作者：
SPRY, CJF
DOI：
10.1098/rstb.1999.0382
发表时间：
1999-02-28
影响因子：
6.3
作者：
Oheim, M;Loerke, D;Stühmer, W
通讯作者：
Stühmer, W
DOI：
10.1083/jcb.51.2.465
发表时间：
1971-11
期刊：
The Journal of cell biology
影响因子：
--
作者：
Röhlich P;Anderson P;Uvnäs B
通讯作者：
Uvnäs B
影响因子：
4.5
作者：
Bokvist, K;Holmqvist, M;Rorsman, P
通讯作者：
Rorsman, P