MOLECULAR MECHANISM OF COLOR RECEPTION BY LIGHT REGULATED BIOLOGICAL CLOCK FOR REPRODUCTION OF ASCIDIANS

所有的动物都必须保护自己不被捕食，它们进化出了各种各样的形态和行为装置来保护自己。其中一个隐藏的秘密是动物对环境的伪装，这种伪装使动物的身体颜色与环境相似。章鱼在皮肤上显示出美丽的颜色和图案。这些身体模式是色彩，纹理，姿势和运动复合体的组合。为了使自己的身体颜色与背景相匹配，它们必须识别环境的颜色。虽然有很多争论，但结论是章鱼是色盲。在本论文中，我们提出章鱼是通过位于其皮肤色素细胞的光感受器来识别环境颜色的。采用时间分辨荧光差成像方法成功地观察到章鱼皮肤中的视网膜蛋白质并确定其定位。接下来，我们通过免疫组织化学检测了章鱼皮肤中视网膜蛋白承载细胞的定位。我们发现抗章鱼视紫红质的多克隆抗体与章鱼皮肤提取物中的56 kDa蛋白有交叉反应。抗章鱼视紫红质细胞多克隆抗体阳性细胞定位于外周细胞。测定了章鱼皮洗涤剂提取液的吸收光谱，在蓝光照射下，吸收峰向红方向移动，在红光照射下，吸收峰恢复到原来的吸收峰。这些结果表明，章鱼皮肤含有视紫红质类色素作为颜色感光器。

AbstractAll animals must defend themselves from predation and they have evolved a great variety of morphological and behavioral devices to do so. One of the crypsis is the camouflage which animal resemble their body color to the environment. Octopus shows beautiful play of color and pattern in the skin. These body pattern is a combination of chromatic, textural, postural and locomotion complexes. In order to mach their body color to background, they must recognize the color of the environment. Though there were a lot of arguments, it is concluded that octopus is color blind. In the present works, we proposed octopus recognized environment color by the photoreceptors located at the choromophore of their skin. Retinal proteins in the skin of octopus were successfully visualized and their localization was determined by the time-resolved fluorescence difference imaging method. Next, we examined the localization of retinal protein bearing cells in the octopus skin by immunohistochemistry. We found that polyclonal antibody against octopus rhodopsin was cross-reacted to the 56 kDa protein in the extract of the octopus skin. The immunopositive cells to the polyclonal antibody against octopus rhodopsin cells localized at the peripheral cellular. Absorption spectra of extract of octopus skin by detergents were measured, Absorption maximum shifted to red upon illumination of blue light and absorption maximum recovered to original spectrum when photoproduct was illuminated red light. These results suggest that octopus skin contain rhodopsin like pigments as color photoreceptor.