Effects of recombinant vertebrate ancient long opsin on reproduction in goldfish, Carassius auratus: profiling green-wavelength light
This study was conducted to identify the possible effect of recombinant vertebrate ancient long (VAL) opsin as a non-visual “photoreceptor” in the deep brain of goldfish, Carassius auratus. In addition, we investigated the effects of green-wavelength light on the predictable reproductive function of VAL-opsin as a green-sensitive pigment in the deep brain. To determine this, we quantified changes in gonadotropin hormone (GTH) [GTHα, follicle stimulating hormone (FSH) and luteinizing hormone (LH)] and estrogen receptor (ER; ERα and ERβ) mRNA expression levels associated with goldfish reproduction as well as changes in plasma FSH, LH, and 17β-estradiol (E2) activities after injection of recombinant VAL-opsin protein in two concentrations (0.1 or 0.5 μg/g body mass) for 4 weeks (injection once weekly) and examined the possible impact of green-wavelength light (500, 520, and 540 nm) on the function of VAL-opsin. As a result, all parameters associated with reproduction significantly increased with time and light-emitting diode (LED) exposure. Based on these results, we suggested that VAL-opsin in the deep brain is involved in goldfish maturation, and it is possible that green-wavelength light improves the ability of VAL-opsin to promote maturation by increasing VAL-opsin expression.
KeywordsGoldfish Green light Maturation Reproduction VAL-opsin
Vertebrate ancient long opsin
This work was supported by the National Research Foundation of Korea grant funded by the Korean government (2014R1A2A2A01002747), and “Development and commercialization of high density low temperature plasma based seawater sterilization pulification system” funded by the Ministry of Oceans and Fisheries, Korea.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Davis LK, Visitacion N, Riley L, Hiramatsu N, Sullivan C, Hirano T, Gordon GE (2009) Effects of o,p′-DDE, heptachlor, and 17β-estradiol on vitellogenin gene expression and the growth hormone/insulin-like growth factor-I axis in the tilapia, Oreochromis mossambicus. Comp Biochem Physiol C 149:507–514Google Scholar
- García-Fernández JM, Cernuda-Cernuda R, Davies WIL, Rodgers J, Turton M, Peirson SN, Follett BK, Halford S, Hughes S, Hankins MW, Foster RG (2015) The hypothalamic photoreceptors regulating seasonal reproduction in birds: a prime role for VA opsin. Front Neuroendocrinol 37:13–28CrossRefPubMedGoogle Scholar
- Karakatsouli N, Papoutsoglou ES, Sotiropoulosa N, Mourtikasa D, Stigen-Martinsena T, Papoutsoglou SE (2010) Effects of light spectrum, rearing density and light intensity on growth performance of scaled and mirror common carp Cyprinus carpio reared under recirculating system conditions. Aqauculture 42:121–127Google Scholar
- Lee YH, Du JL, Yen FP, Lee CY, Dufour S, Huang JD, Sun LT, Chang CF (2001) Regulation of plasma gonadotropin II secretion by sex steroids, aromatase inhibitors, and antiestrogens in the protandrous black porgy, Acanthopagrus schlegeli Bleeker. Comp Biochem Physiol B 129:399–406CrossRefPubMedGoogle Scholar