Figure 1.
An adult male Nile tilapia Oreochromis niloticus (A) and a close-up of the caudal fin (B) showing pigmentation traits.
Figure 2.
Spectral irradiance in fish culture facility.
Table 1.
Primers used in RT-PCR assays.
Figure 3.
Cone opsin expression in tilapia caudal fin.
Using RT-PCR, 7 tilapia cone opsins were detected in tilapia caudal fin but not in the split fin tissue without chromatophores. No detectable signal was found in the non-RT control sample. β-actin was used as a positive control in RT-PCR analysis.
Table 2.
Cone opsin expression profile of tilapia melanophores.
Table 3.
Cone opsin expression profile of tilapia erythrophores.
Figure 4.
Photoresponses of tilapia melanophores.
Individual melanophores were challenged with equal-quanta spectral irradiance (13.9 log photons cm−2 s−1) at one of the stimulating wavelengths (A,B: 380 nm; C,D: 420 nm; E,F: 460 nm; G,H: 500 nm; I,J: 540 nm; K,L: 580 nm; n = 4 at each test wavelength) for 3 minutes. A,C,E,G,I,K: before illumination; B,D,F,H,J,L: after illumination. Scale bar: 40 µm.
Figure 5.
Photoresponses of tilapia erythrophores.
Individual erythrophores were challenged with equal-quanta spectral irradiance (13.9 log photons cm−2 s−1) at one of the stimulating wavelengths (A,B: 380 nm; C,D: 420 nm; E,F: 460 nm; G,H: 500 nm; I,J: 540 nm; K,L: 580 nm; n = 5 at each test wavelength) for 3 minutes. A,C,E,G,I,K: before illumination; B,D,F,H,J,L: after illumination. Scale bar: 20 µm.