ative and Gram-positive bacteria, the halophilic archaebacteria Halobacterium halobium,以及真菌与植物。阿拉伯芥的 1与2亦含有此种结构域，作为促进蓝光基因表现与调整昼夜节律的光受体。The second class are named cryptochrome (Cry), found in species as diverse as Drosophila, Arabidopsis, Synechocystis, a