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CRYPTOCHROME is a blue-light sensor that regulates neuronal firing rate.

ABSTRACT: Light-responsive neural activity in central brain neurons is generally conveyed through opsin-based signaling from external photoreceptors. Large lateral ventral arousal neurons (lLNvs) in Drosophila melanogaster increase action potential firing within seconds in response to light in the absence of all opsin-based photoreceptors. Light-evoked changes in membrane resting potential occur in about 100 milliseconds. The light response is selective for blue wavelengths corresponding to the spectral sensitivity of CRYPTOCHROME (CRY). cry-null lines are light-unresponsive, but restored CRY expression in the lLNv rescues responsiveness. Furthermore, expression of CRY in neurons that are normally unresponsive to light confers responsiveness. The CRY-mediated light response requires a flavin redox-based mechanism and depends on potassium channel conductance, but is independent of the classical circadian CRY-TIMELESS interaction.

SUBMITTER: Fogle KJ

PROVIDER: S-EPMC4418525 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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CRYPTOCHROME is a blue-light sensor that regulates neuronal firing rate.

Fogle Keri J KJ Parson Kelly G KG Dahm Nicole A NA Holmes Todd C TC

Science (New York, N.Y.) 20110303 6023

Light-responsive neural activity in central brain neurons is generally conveyed through opsin-based signaling from external photoreceptors. Large lateral ventral arousal neurons (lLNvs) in Drosophila melanogaster increase action potential firing within seconds in response to light in the absence of all opsin-based photoreceptors. Light-evoked changes in membrane resting potential occur in about 100 milliseconds. The light response is selective for blue wavelengths corresponding to the spectral s ...[more]

PMID: 21385718

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