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Rapid Analysis of Circadian Phenotypes in Arabidopsis Protoplasts Transfected with a Luminescent Clock Reporter
Published on: September 17, 2016
The PAS protein VIVID defines a clock-associated feedback loop that represses light input, modulates gating, and
C Heintzen1, J J Loros, J C Dunlap
1Department of Genetics, Dartmouth Medical School, Hanover, NH 03755, USA.
Cell
|March 10, 2001
Summary
The VVD gene in Neurospora regulates light responses and circadian rhythms. It acts as an early repressor, influencing light adaptation and gating, demonstrating VVD
Area of Science:
- Circadian Biology
- Molecular Genetics
- Mycology
Background:
- The circadian clock regulates daily biological rhythms.
- Light is a key environmental cue for synchronizing circadian clocks.
- Neurospora crassa serves as a model organism for studying circadian rhythms.
Purpose of the Study:
- To investigate the role of the vvd gene in Neurospora's light response and circadian system.
- To elucidate the function of VVD protein, a novel PAS/LOV superfamily member.
- To understand how VVD interacts with the circadian clock to regulate light adaptation and gating.
Main Methods:
- Gene expression analysis of vvd under different light conditions.
- Construction and analysis of vvd mutant strains in Neurospora.
- Assessment of circadian gating and phase-response curves to light stimuli.
Main Results:
- vvd encodes a PAS/LOV protein involved in light responses.
- VVD acts as an early repressor of light-induced genes.
- vvd is clock-controlled, and VVD modulates circadian gating of light responses, including the frq gene.
Conclusions:
- VVD plays a significant role in the Neurospora circadian system, particularly in light adaptation and response gating.
- Although not a core clock component, VVD is crucial for integrating light signals with the circadian clock.
- VVD influences the phase-resetting responses to light, contributing to the robustness of the circadian system.
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