Figure 2. Opsin expression in various tissues of green iguana.

RT-PCR analyses indicate that the iguana parapinopsin gene is expressed in the parietal eye, and the iguana UV cone pigment gene is detected only in the eye. The iguana parietopsin gene is expressed in the parietal eye. The iguana pinopsin gene is detected in the pineal organ but not in the parietal eye. The GAPDH gene was used as an internal standard.