De novo transcriptomics reveal distinct phototransduction signaling components in the retina and skin of a color-changing vertebrate, the hogfish (Lachnolaimus maximus)

• Published in: Journal of Comparative Physiology 2018-05, Vol.204 (5), p.475-485
• Main Authors: Schweikert, Lorian E., Fitak, Robert R., Johnsen, Sönke
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological; Animal Physiology; Animal tissues; Animals; Biomedical and Life Sciences; Cascades; Chromatophores; Color; Color vision; Cyclic GMP; Evolution, Molecular; Female; Fish; Fish Proteins - genetics; Fish Proteins - metabolism; Gene expression; Gene Expression Regulation; Genes; Lachnolaimus maximus; Life Sciences; Neurosciences; Original Paper; Perciformes - genetics; Perciformes - metabolism; Photoreception; Phototransduction; Retina; Retina - metabolism; Rod Opsins - genetics; Rod Opsins - metabolism; Signaling; Skin; Skin - metabolism; Skin Pigmentation - genetics; Transcriptome; Vertebrates; Vision, Ocular - genetics; Zoology
• ISSN: 0340-7594; 1432-1351
• DOI: 10.1007/s00359-018-1254-4

Across diverse taxa, an increasing number of photoreceptive systems are being discovered in tissues outside of the eye, such as in the skin. Dermal photoreception is believed to serve a variety of functions, including rapid color change via specialized cells called chromatophores. In vitro studies of this system among color-changing fish have suggested the use of a phototransduction signaling cascade that fundamentally differs from that of the retina. Thus, the goal of this study was to identify phototransduction genes and compare their expression in the retina and skin of a color-changing fish, the hogfish Lachnolaimus maximus . De novo transcriptomics revealed the expression of genes that may underlie distinct, yet complete phototransduction cascades in L. maximus retina and skin. In contrast to the five visual opsin genes and cGMP-dependent phototransduction components expressed in the retina of L. maximus , only a single short-wavelength sensitive opsin (SWS1) and putative cAMP-dependent phototransduction components were expressed in the skin. These data suggest a separate evolutionary history of phototransduction in the retina and skin of certain vertebrates and, for the first time, indicate an expression repertoire of genes that underlie a non-retinal phototransduction pathway in the skin of a color-changing fish.