蓝光诱导近海硬骨鱼类黑色隐蔽伪装色形成的机理

鱼体背部体色深、腹部体色浅，是一种伪装色，称为隐蔽伪装色，对于鱼类的避敌和摄食十分重要。对于鱼类隐蔽伪装色的形成，目前尚缺乏深入的研究。硬骨鱼类的隐蔽伪装色，以背、腹部黑色素细胞多寡呈现的黑色隐蔽伪装色最为普遍。我们发现一种近海底层硬骨鱼类的黑色隐蔽伪装色形成，受蓝光的诱导，由于海面蓝光能渗透到近海各种深度，近海硬骨鱼类黑色隐蔽伪装色的形成可能普遍受蓝光的诱导，因此，深入研究蓝光诱导黑色隐蔽伪装色形成的机理，十分重要。本项目提出了蓝光诱导黑色隐蔽伪装色形成的“蓝光-视黄酸-ASIP1”假说，解释来自海面透射下来的蓝光，如何影响鱼体背、腹部黑色素细胞数量形成的差异，并借助各种技术手段验证，明确“蓝光-视黄酸-ASIP1”调控机制在近海硬骨鱼类黑色隐蔽伪装色形成中的作用，进而在分子层面探究近海硬骨鱼类黑色隐蔽伪装色形成的适应进化机制，以更好地理解其在避敌和摄食方面的重要作用。

Countershading is a method of camouflage with a vertical luminance gradient from a dark back to a light belly, is perhaps the most common coloration phenotype in the animal kingdom. In bony fishes, countershading plays an important role in social events, such as predator avoidance and prey capture. Countershading is a type of morphological color patterns, where the areas that are typically exposed to more light are darker with more melanophores in bony fishes. So far, how light help animals to develop countershading is still unclear. In a previous study, we found the formation of melanophores-determined dorso-ventral countershading induced by blue light during the development of Paralichthys olivaceus, a marine benthic bony fish. Since blue light from sea surface can reach to over 200 meter depth, the formation of melanophores-determined countershading in various kinds of bony fishes living in offshore might be induced by blue light. In order to better understand the mechanism of countershading development in marine bony fishes, in this research program, we will investigate the morphological feature of melanophores-determined countershading in common marine bony fishes in China, and propose a hypothesis of “Bluelight- 9cRA-ASIP1” to explain how blue light induces the development of countershading, and test the hypothesis in this research using blue light and various means of genetic interference. The research will uncover the key downstream signals of blue light regulation in development of melanophores-determined dorso-ventral countershading. Moreover, we hope can better understand the evolutionary mechanism of countershading in various kinds of marine bony fishes.