Hatskelzon L, Dalal B I, Shalev A, Robertson C, Gerrard J M
Manitoba Institute of Cell Biology, Winnipeg, Canada.
Lab Invest. 1993 May;68(5):509-19.
The identification and characterization of granule membrane proteins are becoming increasingly important in understanding the packaging and secretory function of granules and characterizing diseases involving granules. A granule membrane protein, granulophysin, has recently been identified in the membranes of platelet dense granules, organelles that contain stored ADP, ATP, serotonin, and calcium. Antibodies that recognize granulophysin also stain granules of monocytes, neutrophils, and lymphokine activated killer cells.
In the present study, the distribution of epitopes recognized by antigranulophysin monoclonal antibodies in human tissues was investigated using immunohistochemistry on paraffin sections. Quantitation of the protein was also performed by enzyme-linked immunosorbent assay. The protein was also analyzed in various tissues using Western blotting.
Granulophysin was localized to the granules of skin melanocytes, neurons, endocrine gland cells, exocrine glands (except mucin producing cells), and surface lining cells. Analysis by Western blots revealed a typical staining pattern for granulophysin in lung, adrenal gland, liver, brain, prostate, and pituitary. Atypical bands were present in the pancreas head (47 kDa) and skeletal muscle (34 kDa). A clear distinction was demonstrated between granulophysin and synaptophysin through both immunochemistry and blotting, despite the known cross-reactivity of these two proteins.
The findings demonstrate that granulophysin is a widely distributed protein that is frequently associated with granules. We speculate that it may be critical in granule function.
在理解颗粒的包装和分泌功能以及表征涉及颗粒的疾病方面，颗粒膜蛋白的鉴定和特性研究变得越来越重要。一种颗粒膜蛋白，即颗粒溶素，最近在血小板致密颗粒的膜中被鉴定出来，血小板致密颗粒是含有储存的二磷酸腺苷（ADP）、三磷酸腺苷（ATP）、血清素和钙的细胞器。识别颗粒溶素的抗体也能使单核细胞、中性粒细胞和淋巴因子激活的杀伤细胞的颗粒着色。
在本研究中，使用石蜡切片免疫组织化学方法研究了抗颗粒溶素单克隆抗体识别的表位在人体组织中的分布。还通过酶联免疫吸附测定法对该蛋白进行了定量分析。同时使用蛋白质印迹法在各种组织中对该蛋白进行了分析。
颗粒溶素定位于皮肤黑素细胞、神经元、内分泌腺细胞、外分泌腺（产生粘蛋白的细胞除外）和表面衬里细胞的颗粒中。蛋白质印迹分析显示，颗粒溶素在肺、肾上腺、肝脏、脑、前列腺和垂体中有典型的染色模式。在胰头（47 kDa）和骨骼肌（34 kDa）中存在非典型条带。尽管已知这两种蛋白有交叉反应性，但通过免疫化学和印迹法都清楚地证明了颗粒溶素和突触囊泡蛋白之间的区别。
研究结果表明颗粒溶素是一种广泛分布的蛋白，且常与颗粒相关。我们推测它可能在颗粒功能中起关键作用。
