ZFIN ID: ZDB-PUB-061229-20
Mitogen-associated protein kinase- and protein kinase A-dependent regulation of rhodopsin promoter expression in zebrafish rod photoreceptor cells
Yu, C.J., Gao, Y., Willis, C.L., Li, P., Tiano, J.P., Nakamura, P.A., Hyde, D.R., and Li, L.
Date: 2007
Source: Journal of neuroscience research   85(3): 488-496 (Journal)
Registered Authors: Hyde, David R., Li, Lei
Keywords: MAPK, PKA, rhodopsin, dopamine, light, photoreceptor, zebrafish
MeSH Terms:
  • Animals
  • Cyclic AMP-Dependent Protein Kinases/metabolism*
  • Gene Expression Regulation
  • Kinetics
  • Light
  • Mitogen-Activated Protein Kinases/metabolism*
  • Promoter Regions, Genetic/radiation effects
  • Retinal Rod Photoreceptor Cells/physiology*
  • Rhodopsin/genetics*
  • Transcription, Genetic
  • Zebrafish
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
PubMed: 17183589 Full text @ J. Neurosci. Res.
Mitogen-associated protein kinase (MAPK)- and protein kinase A (PKA)-dependent signal transductions play important roles in the regulation of gene expression. Both MAPK and PKA pathways can be activated by light exposure. In this study, we investigated the effect of light on MAPK and PKA signal transduction and their roles in the regulation of rhodopsin promoter expression by using transgenic zebrafish [Tg(rhod::GFP)]. The Tg(rhod::GFP) fish express short half-life GFP that is under the transcriptional control of the zebrafish rhodopsin promoter and can therefore be used for in vivo studies of rhodopsin gene transcription in live cells. Blue light plays a role in the regulation of rhodopsin promoter expression via an MAPK-mediated signal transduction cascade. Blue light excites cryptochromes (CRY), which activate the downstream PKC-dependent MAPK signal pathway. White light, on the other hand, regulates rhodopsin promoter expression via a G-protein-coupled cAMP-dependent PKA pathway. White light promotes dopamine release in the retina, which activates dopamine receptors and the downstream PKA pathway. Blocking MAPK signaling diminishes the blue light-induced increases in rhodopsin promoter expression, but this treatment has no effect on white light-mediated rhodopsin promoter expression. Conversely, blocking the PKA pathway diminishes the white light-induced rhodopsin promoter expression but does not affect rhodopsin promoter expression regulated by blue light. Together, the data suggest that MAPK and PKA regulate rhodopsin transcription through parallel signal transduction pathways.