ANIMAL-CELL LYSOSOMES RAPIDLY EXCHANGE MEMBRANE-PROTEINS
ANIMAL-CELL LYSOSOMES RAPIDLY EXCHANGE MEMBRANE-PROTEINS
复制标题
DOI：
10.1073/pnas.85.11.3860
复制
发表时间：
1988-06-01
影响因子：
11.1
通讯作者：
STORRIE, B
中科院分区：
文献类型：
--
作者：
DENG, YP;STORRIE, B
溶酶体已被选为研究细胞器群体内天然膜蛋白交换的模型。通过水疱性口炎病毒介导的细胞融合将异源溶酶体聚集在一起。采用种特异性单克隆抗体间接免疫荧光法观察溶酶体膜蛋白的分布。小鼠溶酶体膜蛋白LAMP-2和人溶酶体膜蛋白HLAMP-B可转移至中国仓鼠卵巢细胞的蔗糖体（蔗糖肿胀溶酶体）。这种转移发生在环己亚胺的存在下。在小鼠(3T3)-大鼠（正常大鼠肾）细胞融合过程中，观察了大鼠溶酶体膜蛋白LAMP-2和LIMP I在天然溶酶体间的交换。融合后1.5-2小时内观察到广泛的转移/交换，这与溶酶体之间的内吞内容交换动力学一致。膜蛋白和溶酶体之间的内容物转移都被微管干扰物诺可达唑（nocodazole）所抑制，向蔗糖肿胀溶酶体的内吞噬递送也是如此。在诺可唑存在下，管状溶酶体消失。管状溶酶体和微管对于转移/交换可能都很重要。这里开发的种间细胞融合/单克隆抗体方法应该很容易适用于确定膜蛋白交换是否是其他细胞器（如高尔基体和线粒体）的特性。
The lysosome has been chosen as a model to study the exchange of native membrane proteins within an organelle population. Heterologous lysosomes were brought together by vesicular stomatitis virus-mediated cell fusion. The distribution of lysosomal membrane protein was visualized by indirect immunofluorescence using species-specific monoclonal antibody. LAMP-2, a mouse lysosomal membrane protein, and HLAMP-B, a human lysosomal membrane protein, were found to transfer to Chinese hamster ovary cell sucrosomes (surcrose-swollen lysosomes). This transfer occurred in the presence of cycloheximide. The exchange of LAMP-2 and LIMP I, a rat lysosomal membrane protein, was observed between native lysosomes in a mouse (3T3)-rat (normal rat kidney) cell fusion. Extensive transfer/exchange was observed within 1.5-2 hr postfusion, which is consistent with the kinetics of endocytic content exchange between lysosomes. Both membrane protein and content transfer between lysosomes were inhibited by nocodazole, a disrupter of microtubules, as was endocytic delivery to sucrose-swollen lysosomes. In the presence of nocodazole, tubular lysosomes disappeared. Both tubular lysosomes and microtubules may be important for the transfer/exchange. The interspecies cell fusion/monoclonal antibody approach developed here should be readily applicable to determining if membrane protein exchange is a property of other organelles such as Golgi apparatus and mitochondria.