retina,olfactory vesicle, olfactory vesicle, anterior dorsal spinal cord,proctodeum, caudal notochord, and pharyngeal arches | ： | 2.5 kb upstream of the Cyp26a1 translational start drives EYFP expression. YFP expressed in pattern of the transgene is mainly in retina, cells in olfactory vesicle, anterior dorsal spinal cord, proctodeum, caudal notochord, and pharyngeal arches |