Phototaxis - Stimulation by Lights
Important Papers
[1] Light-sensitive neurons and channels mediate phototaxis in C. elegans
- Alex Ward, Jie Liu, Zhaoyang Feng, X Z Shawn Xu (University of Michigan)
- Nature Neuroscience 11, 916 - 922 (2008)
- They identified a group of ciliary sensory neurons as candidate photoreceptor cells for mediating phototaxis. Furthermore, they found that light excited photoreceptor cells by evoking a depolarizing conductance carried by cyclic guanosine monophosphate (cGMP)-sensitive cyclic nucleotide–gated (CNG) channels, revealing a conservation in phototransduction between worms and vertebrates. These results identify a new sensory modality in C. elegans and suggest that animals living in dark environments without light-sensing organs may not be presumed to be light insensitive.
[2] C. elegans phototransduction requires a G protein–dependent cGMP pathway and a taste receptor homolog
- Jie Liu et al, X Y Shawn Xu Group (University of Michigan)
- Nature Neuroscience 13, 715–722 (2010)
- They found that phototransduction in ASJ is a G protein–mediated process and requires membrane-associated guanylate cyclases, but not typical phosphodiesterases. In addition, They found that C. elegans phototransduction requires LITE-1, a candidate photoreceptor protein known to be a member of the invertebrate taste receptor family. Their genetic, pharmacological and electrophysiological data suggest a model in which LITE-1 transduces light signals in ASJ via G protein signaling, which leads to upregulation of the second messenger cGMP, followed by opening of cGMP-sensitive CNG channels and stimulation of photoreceptor cells.
[3] Photoreceptors: unconventional ways of seeing
- Naryttza N. Diaz, Simon G. Sprecher
- Curr Biol. 2011 Jan 11;21(1):R25-7
- Animals perceive light typically by photoreceptor neurons assembled in eyes, but some also use non-eye photosensory neurons. Multidendritic neurons in the body wall of Drosophila larvae have now been shown to use an unconventional phototransduction mechanism to sense light.