Membrane glycoproteins common to vesicles and melanosomes in mouse melanoma cells.
Membrane glycoproteins common to vesicles and melanosomes in mouse melanoma cells.
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小鼠黑色素瘤细胞中囊泡和黑素体常见的膜糖蛋白。
DOI：
10.1111/j.1600-0749.1990.tb00368.x
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Pawelek,JM
中科院分区：
文献类型：
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作者：
Orlow,SJ;Chakraborty,AK;Pawelek,JM
自Herrmann和Boss（1945）和Lerner et al.（1949）证明了酪氨酸酶的颗粒性质，已经认识到黑色素是在称为黑素体的亚细胞细胞器中合成的或与其相关。Seiji和同事（1963）分离出黑素体，并描述了其成熟的四个阶段（I-IV）。黑素体的成熟涉及一类包被囊泡，如电子显微镜研究所示（Maul，1969; Novikoff et al.，1968年; Maul和Brumbaugh，1971年）。黑素生成的关键酶似乎起源于GEXL（高尔基体-内质网-溶酶体）网络，随后与I1期黑素体融合（Maul，1969; Novikoff等，1968年; Maul和Brumbaugh，1971年）。最近，通过利用从脑中纯化包被囊泡的技术（Usami等人，1984），已经表明源自鼠和仓鼠黑色素瘤细胞的囊泡不仅相对于来自那些细胞的其它膜级分高度富集酪氨酸酶活性，而且还含有高水平的多巴色素转化因子和γ-谷氨酰转移酶（Chakraborty等人，1989年）。这两种酶都被认为是合成真黑素和褐黑素的重要调节因子。此外，已经证明两种黑素生成前体，二羟基吲哚和二羟基吲哚-2-羧酸存在于囊泡部分中（Hatta等人，1988年）。总之，这些数据表明，在启动黑素生成的未成熟的黑素体，他们被认为是融合的包被囊泡的关键作用。这个模型预测，某些蛋白质存在于包被囊泡“捐赠”黑素体囊泡融合后，与这些细胞器。Cloudman鼠黑素瘤细胞系提供了用于研究该过程的极好系统：在培养物中，未处理的细胞是无黑素的并且仅含有阶段1-11黑素体（Pawelek等人，1973年）。在酪氨酸酶活性的组织化学检查中没有观察到反应产物，在细胞提取物中也不能证明这种活性。然而，在用促黑素细胞激素（MSH）治疗的数小时内，
Since Herrmann and Boss (1945) and Lerner et al.(1949) demonstrated the particulate nature of tyrosinase, it has been recognized that melanin is synthesized in or associated with a subcellular organelle termed the melanosome. Seiji and coworkers (1963) isolated the melanosome, and delineated four stages in its maturation (I-IV). The maturation of melanosomes involves a class of coated vesicles, as suggested from electron microscopic studies (Maul, 1969; Novikoff et al., 1968; Maul and Brumbaugh, 1971). a key enzyme in melanogenesis. appeared to arise from the GEXL (Golgi-Endoplasmic reticulum-lysosomal) network and later fuse with Stage I1 melanosomes (Maul, 1969; Novikoff et al., 1968; Maul and Brumbaugh, 1971). Recently, by utilizing techniques for the purification of coated vesicles from brain (Usami et al., 1984), it has been shown that vesicles derived from murine and hamster melanoma cells are not only highly enriched for tyrosinase activity over other membranous fractions from those cells, but also contain high levels of dopachrome conversion factor and gammaglutamyl transferase (Chakraborty et al., 1989). Both of these enzymes are believed to be important regulatory factors in the synthesis of both euand pheomelanin. In addition, two melanogenic precursors, dihydroxyindole and dihydroxyindole-2-carboxylic acid, have been demonstrated to be present in the vesicular fraction (Hatta et al., 1988). Taken together, such data suggest a key role for coated vesicles in initiating melanogenesis in the immature melanosomes with which they are believed to fuse. This model predicts that certain proteins present in coated vesicles are" donated" to melanosomes upon vesicular fusion with those organelles. The Cloudman murine melanoma cell line provides an excellent system for studying this process: In culture, untreated cells are amelanotic and contain only Stage 1-11 melanosomes (Pawelek et al., 1973). No reaction product is seen upon histochemical examination for tyrosinase activity, nor can such activity be demonstrated in cell extracts. Within hours of treat ent with melanocyte-stimulating hormone (MSH)', however, tyrosinase activity within the