Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Curr Biol. 2012 Nov 6;22(21):2042-7. doi: 10.1016/j.cub.2012.08.016. Epub 2012 Sep 20.

Deep brain photoreceptors control light-seeking behavior in zebrafish larvae.

Author information

  • 1Developmental Biology Unit, Faculty of Biology, BIOSS Centre for Biological Signalling Studies and FRIAS Freiburg Institute for Advanced Studies, University of Freiburg, 79104 Freiburg, Germany.

Abstract

Most vertebrates process visual information using elaborately structured photosensory tissues, including the eyes and pineal. However, there is strong evidence that other tissues can detect and respond to photic stimuli. Many reports suggest that photosensitive elements exist within the brain itself and influence physiology and behavior; however, a long-standing puzzle has been the identity of the neurons and photoreceptor molecules involved. We tested whether light cues influence behavior in zebrafish larvae through deep brain photosensors. We found that larvae lacking eyes and pineal perform a simple light-seeking behavior triggered by loss of illumination ("dark photokinesis"). Neuroanatomical considerations prompted us to test orthopedia (otpa)-deficient fish, which show a profound reduction in dark photokinesis. Using targeted genetic ablations, we narrowed the photosensitive region to neurons in the preoptic area. Neurons in this region express several photoreceptive molecules, but expression of the melanopsin opn4a is selectively lost in otpa mutants, suggesting that opn4a mediates dark photokinesis. Our findings shed light on the identity and function of deep brain photoreceptors and suggest that otpa specifies an ancient population of sensory neurons that mediate behavioral responses to light.

Copyright © 2012 Elsevier Ltd. All rights reserved.

Comment in

PMID:
23000151
[PubMed - indexed for MEDLINE]
PMCID:
PMC3494761
Free PMC Article

Images from this publication.See all images (3)Free text

Figure 1
Figure 2
Figure 3
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Write to the Help Desk