血小板α颗粒和致密核心颗粒分泌的分子剖析

Molecular dissection of alpha- and dense-core granule secretion of platelets.

作者信息

Yoshioka A, Horiuchi H, Shirakawa R, Nishioka H, Tabuchi A, Higashi T, Yamamoto A, Kita T

机构信息

Department of Geriatric Medicine, Graduate School of Medicine, Kyoto University, Japan.

出版信息

Ann N Y Acad Sci. 2001 Dec;947:403-6. doi: 10.1111/j.1749-6632.2001.tb03973.x.

DOI:10.1111/j.1749-6632.2001.tb03973.x

PMID:11795301

Abstract

Upon activation, platelets release many active substances stored in alpha- and dense-core granules. However, the molecular mechanisms governing the regulated exocytosis are not yet fully understood. We have established an assay system using streptolysin-O-permeabilized platelets to analyze the Ca2+-induced secretions of von Willebrand factor stored in alpha-granules and [3H]5-hydroxytryptamine (5-HT) in dense-core granules. Using the assay, we found that small GTPase Rab4 regulates alpha-, but not dense-core, granule secretion in platelets. Furthermore, we purified a cytosolic essential protein and currently are analyzing its function.

摘要

血小板激活后会释放许多储存在α颗粒和致密核心颗粒中的活性物质。然而，调控分泌性胞吐作用的分子机制尚未完全明确。我们建立了一种利用链球菌溶血素O通透化血小板的检测系统，以分析Ca2+诱导的α颗粒中储存的血管性血友病因子以及致密核心颗粒中[3H]5-羟色胺（5-HT）的分泌情况。通过该检测，我们发现小GTP酶Rab4调节血小板中α颗粒而非致密核心颗粒的分泌。此外，我们纯化了一种胞质必需蛋白，目前正在分析其功能。