Hierarchies in light sensing and dynamic interactions between ocular and extraocular sensory networks in a flatworm.

ABSTRACT: Light sensing has independently evolved multiple times under diverse selective pressures but has been examined only in a handful among the millions of light-responsive organisms. Unsurprisingly, mechanistic insights into how differential light processing can cause distinct behavioral outputs are limited. We show how an organism can achieve complex light processing with a simple "eye" while also having independent but mutually interacting light sensing networks. Although planarian flatworms lack wavelength-specific eye photoreceptors, a 25 nm change in light wavelength is sufficient to completely switch their phototactic behavior. Quantitative photoassays, eye-brain confocal imaging, and RNA interference/knockdown studies reveal that flatworms are able to compare small differences in the am

SUBMITTER: Shettigar N 

PROVIDER: S-EPMC5533540 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature