Possible Involvement of Cone Opsins in Distinct Photoresponses of Intrinsically Photosensitive Dermal Chromatophores in Tilapia Oreochromis Niloticus
Overview
Affiliations
Dermal specialized pigment cells (chromatophores) are thought to be one type of extraretinal photoreceptors responsible for a wide variety of sensory tasks, including adjusting body coloration. Unlike the well-studied image-forming function in retinal photoreceptors, direct evidence characterizing the mechanism of chromatophore photoresponses is less understood, particularly at the molecular and cellular levels. In the present study, cone opsin expression was detected in tilapia caudal fin where photosensitive chromatophores exist. Single-cell RT-PCR revealed co-existence of different cone opsins within melanophores and erythrophores. By stimulating cells with six wavelengths ranging from 380 to 580 nm, we found melanophores and erythrophores showed distinct photoresponses. After exposed to light, regardless of wavelength presentation, melanophores dispersed and maintained cell shape in an expansion stage by shuttling pigment granules. Conversely, erythrophores aggregated or dispersed pigment granules when exposed to short- or middle/long-wavelength light, respectively. These results suggest that diverse molecular mechanisms and light-detecting strategies may be employed by different types of tilapia chromatophores, which are instrumental in pigment pattern formation.
Yu H, Chen H, Wang X, Zhang Y, Tan Y, Wang L Int J Mol Sci. 2024; 25(14).
PMID: 39062755 PMC: 11277425. DOI: 10.3390/ijms25147513.
Dynamic light filtering over dermal opsin as a sensory feedback system in fish color change.
Schweikert L, Bagge L, Naughton L, Bolin J, Wheeler B, Grace M Nat Commun. 2023; 14(1):4642.
PMID: 37607908 PMC: 10444757. DOI: 10.1038/s41467-023-40166-4.
Al-Soudy A, Maselli V, Galdiero S, Kuba M, Polese G, Di Cosmo A Biology (Basel). 2021; 10(9).
PMID: 34571813 PMC: 8465341. DOI: 10.3390/biology10090936.
Light organ photosensitivity in deep-sea shrimp may suggest a novel role in counterillumination.
Bracken-Grissom H, DeLeo D, Porter M, Iwanicki T, Sickles J, Frank T Sci Rep. 2020; 10(1):4485.
PMID: 32161283 PMC: 7066151. DOI: 10.1038/s41598-020-61284-9.
Expression of extraocular genes and light-dependent basal activity of blind cavefish.
Simon N, Fujita S, Porter M, Yoshizawa M PeerJ. 2019; 7:e8148.
PMID: 31871836 PMC: 6924323. DOI: 10.7717/peerj.8148.