Mircheff A K, Lu C C
Am J Physiol. 1984 Dec;247(6 Pt 1):G651-61. doi: 10.1152/ajpgi.1984.247.6.G651.
We combined separation procedures based on three independent physical properties, sedimentation coefficient, density, and partitioning in an aqueous polymer two-phase system, to generate a three-dimensional subcellular fractionation of rat exorbital lacrimal gland. The distributions of protein and five enzymatic markers define a total of 13 physically and biochemically distinct membrane populations. These include epithelial cell apical membranes, purified 330-fold with respect to the initial homogenate; basal-lateral membranes, purified 80-fold; mitochondria, purified 19-fold; and a major endoplasmic reticulum population, purified 22-fold. Also apparent is a major Golgi population, which is extensively overlapped by other membrane populations; two populations that can be visualized as forming transitions between the endoplasmic reticulum and Golgi membranes; and several populations with unknown subcellular origins. Most of the markers have complex distributions among the isolated membrane populations; this complexity is consistent with current concepts of the synthesis and recycling of membrane constituents and the regulation of cytosolic electrolyte activities.
我们结合了基于三种独立物理性质的分离程序，即沉降系数、密度以及在水性聚合物双相系统中的分配，以生成大鼠眶外泪腺的三维亚细胞分级分离。蛋白质和五种酶标志物的分布定义了总共13个物理和生化性质不同的膜群体。这些包括上皮细胞顶端膜，相对于初始匀浆纯化了330倍；基底外侧膜，纯化了80倍；线粒体，纯化了19倍；以及主要的内质网群体，纯化了22倍。同样明显的是一个主要的高尔基体群体，它与其他膜群体广泛重叠；两个群体可被视为在内质网和高尔基体膜之间形成过渡；还有几个亚细胞起源未知的群体。大多数标志物在分离的膜群体中具有复杂的分布；这种复杂性与当前关于膜成分的合成和循环以及细胞质电解质活性调节的概念一致。
