Fukuzawa T, Obika M
Department of Biology, Keio University, Yokohama, Japan.
Pigment Cell Res. 1995 Feb;8(1):1-9. doi: 10.1111/j.1600-0749.1995.tb00768.x.
Little is known about cell-cell communication in pigment cells, whereas a number of signalling molecules have been implicated to control their migration, differentiation, and proliferation. We set out to investigate the expression of cell adhesion molecules (CAMs) in the three different types of pigment cells in poikilotherms, Oryzias latipes and Xenopus laevis. In the present experiments, the expression of N-CAM and N-cadherin in the pigment cells in vitro was examined by immunocytochemistry. Melanophores and xanthophores were isolated and cultured from scales or skins, while iridophores were harvested from skins or peritoneum. The results showed that N-CAM and N-cadherin were specifically expressed in xanthophores, but not in melanophores or iridophores in both O. latipes and X. laevis. N-CAM and N-cadherin basically colocalized in the restricted regions of xanthophores, although the N-caderin-expressed region was broader than the N-CAM-expressed region in the same cell. The incidence of N-cadherin expression was higher than that of N-CAM expression. N-CAM and N-cadherin were expressed at the tip or the base of dendrites, or at the edge between dendrites in dendritic xanthophores. N-CAM and N-cadherin usually localized in small and narrow regions of xanthophores. This distribution pattern was essentially similar in xanthophores with round morphology, which exhibited spot, band, or semicircular immunoreactive regions on the peripheral edge of the cells. The difference in the distribution of pigment granules within the cells, culture period, fixatives, or immunofluorescent markers used in the experiments did not alter the immunostaining pattern.
关于色素细胞中的细胞间通讯，我们所知甚少，然而已有多种信号分子被认为参与调控其迁移、分化和增殖。我们着手研究变温动物青鳉和非洲爪蟾中三种不同类型色素细胞中细胞黏附分子（CAMs）的表达。在本实验中，通过免疫细胞化学检测了体外培养的色素细胞中N-CAM和N-钙黏蛋白的表达。从鳞片或皮肤中分离并培养黑素细胞和黄色素细胞，而从皮肤或腹膜中获取虹彩细胞。结果表明，在青鳉和非洲爪蟾中，N-CAM和N-钙黏蛋白在黄色素细胞中特异性表达，而在黑素细胞或虹彩细胞中不表达。N-CAM和N-钙黏蛋白基本共定位于黄色素细胞的特定区域，尽管在同一细胞中N-钙黏蛋白的表达区域比N-CAM的表达区域更宽。N-钙黏蛋白的表达发生率高于N-CAM的表达发生率。N-CAM和N-钙黏蛋白在树突状黄色素细胞的树突尖端或基部，或树突之间的边缘表达。N-CAM和N-钙黏蛋白通常定位于黄色素细胞的小而窄的区域。在形态为圆形的黄色素细胞中，这种分布模式基本相似，在细胞的外周边缘呈现斑点、带状或半圆形免疫反应区域。细胞内色素颗粒分布的差异、培养时间、固定剂或实验中使用的免疫荧光标记物均未改变免疫染色模式。
