Manipulation of Disulfide Bonds Differentially Affects the Intracellular Transport, Sorting, and Processing of Neuroendocrine Secretory Proteins
Manipulation of Disulfide Bonds Differentially Affects the Intracellular Transport, Sorting, and Processing of Neuroendocrine Secretory Proteins
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二硫键的操作不同地影响神经内分泌分泌蛋白的细胞内运输、分类和加工
DOI：
10.1046/j.1471-4159.1998.71010402.x
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发表时间：
1998
影响因子：
4.7
通讯作者：
G. Martens
中科院分区：
文献类型：
--
作者：
A. M. Van Horssen;F. V. van Kuppeveld;G. Martens
摘要：为了研究防止二硫键形成是否会影响调节分泌途径中一组不同神经内分泌蛋白的细胞内转运、分选和加工，我们用巯基还原剂二硫苏糖醇处理了爪蟾中间垂体。脉冲追踪孵育结合免疫沉淀分析用于监测激素原阿黑皮素原（POMC）、激素原转化酶PC 2及其辅助蛋白7 B2以及分泌颗粒蛋白III的命运。POMC和proPC 2中二硫键的操纵阻断了它们向trans-Golgi网络的转运，并强烈抑制了它们的加工。7 B2中单个二硫键的还原不影响其转运和裂解，但导致其误分选到组成性分泌途径。此外，proPC 2和7 B2之间的联系也被阻止。二硫苏糖醇不影响运输，分选和分泌颗粒蛋白III，其中缺乏二硫键裂解。当还原剂被洗掉时，POMC加工、proPC 2成熟以及proPC 2和7 B2之间的缔合被重新建立。总的来说，我们的研究结果表明，操纵二硫键差异影响神经内分泌蛋白的命运，在他们的运输通过分泌途径。
Abstract: To investigate if the prevention of disulfide bond formation affects the intracellular transport, sorting, and processing of a distinct set of neuroendocrine proteins in the regulated secretory pathway, we have treated Xenopus intermediate pituitaries with the thiol‐reducing agent dithiothreitol. Pulse‐chase incubations in combination with immunoprecipitation analysis were used to monitor the fates of the prohormone proopiomelanocortin (POMC), prohormone convertase PC2 and its helper protein 7B2, as well as secretogranin III. Manipulation of the disulfide bonds in POMC and proPC2 blocked their transport to the trans‐Golgi network and strongly inhibited their processing. Reduction of the single disulfide bond in 7B2 did not disturb its transport and cleavage, but caused its missorting to the constitutive secretory pathway. Moreover, the liaison between proPC2 and 7B2 was prevented. Dithiothreitol did not affect transport, sorting, and cleavage of secretogranin III, which lacks disulfide bonds. When the reducing agent was washed away, POMC processing, proPC2 maturation, and the association between proPC2 and 7B2 were reestablished. Collectively, our findings indicate that manipulation of disulfide bonds differentially affects the fates of neuroendocrine proteins during their transit through the secretory pathway.
DOI：
10.1042/bj2990001
发表时间：
1994-04
期刊：
The Biochemical journal
影响因子：
--
作者：
P. Halban;J. Irminger
通讯作者：
P. Halban;J. Irminger
DOI：
--
发表时间：
1993-09
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
H. F. Lodish;N. Kong
通讯作者：
H. F. Lodish;N. Kong