September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
The role of thyroid hormone in the differential regulation of tandemly duplicated opsin genes in zebrafish
Author Affiliations & Notes
  • Robert Mackin
    Biology, University of Idaho, Moscow, Idaho, United States
  • Carmina Gutierrez
    Biology, University of Idaho, Moscow, Idaho, United States
  • Diana Mitchell
    Biology, University of Idaho, Moscow, Idaho, United States
  • Deborah L Stenkamp
    Biology, University of Idaho, Moscow, Idaho, United States
  • Footnotes
    Commercial Relationships   Robert Mackin, None; Carmina Gutierrez, None; Diana Mitchell, None; Deborah Stenkamp, None
  • Footnotes
    Support  NIH R01 EY012146, NIH Idaho INBRE P20 GM103408, IBEST P30 GM103324, NSF REU Site award DBI #1460696
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 576. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Robert Mackin, Carmina Gutierrez, Diana Mitchell, Deborah L Stenkamp; The role of thyroid hormone in the differential regulation of tandemly duplicated opsin genes in zebrafish. Invest. Ophthalmol. Vis. Sci. 2016;57(12):576.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose :
Human trichromatic color vision requires a mechanism for differential expression of the tandemly-duplicated LWS/MWS (long- and medium-wavelength sensitive) cone opsin genes, such that they are each expressed in a subset of cones. Our previous published findings have suggested that the trans-acting nuclear signaling molecule retinoic acid (RA) is involved in the differential regulation of tandemly duplicated LWS cone opsins in zebrafish. Here we test the hypotheses that the nuclear signaling molecule thyroid hormone (T3) is also involved in this regulatory activity.

Methods : Zebrafish embryos were treated with DMSO (control), 4nM, 20nM, or 100nM T3 from 48 hours post fertilization (hpf) to 96 hpf. Expression of LWS1 and LWS2 was measured by qPCR. To visualize LWS expression, in-situ hybridization using gene specific probes was performed on cryosections. In addition, the transgenic line LWS:PAC(H) was utilized. This line reports LWS1 with GFP and LWS2 with RFP, and these reporters were imaged in whole-mounted embryo eyes with confocal microscopy.

Results : In control embryos, all measures of LWS2 showed widespread and high levels of expression, while all measures of LWS1 showed little or no expression. In embryos treated with 100nM T3, LWS1 expression increased by 10 fold (p=2.84E-07) and was widespread throughout the retina, while LWS2 expression decreased by 5 fold (p=2.16E-07). Embryos treated with 20nM T3 also revealed a significant 9 fold increase in LWS1 (p=2.16E-07) and no significant change in LWS2 (p= 0.98). The effects of 20nM and 100nM T3 were each more robust than the reported effects of 300nM RA. Interestingly, 4nM T3 treatments increased both LWS1 by 7 fold (p=1.12E-06) and LWS2 by 4 fold (p=9.39E-05).

Conclusions : These results significantly extend previous findings that nuclear signaling molecules influence differential regulation of tandemly duplicated cone opsin genes. Our results suggest that the first member of the LWS array (LWS1) responds to exogenous T3 in a dosage-dependent manner. However, LWS2 expression is decreased with 100nM T3 and increased with 4nM T3, suggesting a more complex control mechanism. These findings provide further evidence that the differential regulation of tandemly duplicated cone opsin genes may not rely solely upon stochastic events, but is one in which trans-acting factors can influence differential expression.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×