Magnetic intensity affects cryptochrome-dependent responses in Arabidopsis thaliana

@article{Ahmad2006MagneticIA,
  title={Magnetic intensity affects cryptochrome-dependent responses in Arabidopsis thaliana},
  author={Margaret Ahmad and Paul Galland and Thorsten Ritz and Roswitha Wiltschko and Wolfgang Wiltschko},
  journal={Planta},
  year={2006},
  volume={225},
  pages={615-624}
}
Cryptochromes are blue-light absorbing photoreceptors found in many organisms where they have been involved in numerous growth, developmental, and circadian responses. In Arabidopsis thaliana, two cryptochromes, CRY1 and CRY2, mediate several blue-light-dependent responses including hypocotyl growth inhibition. Our study shows that an increase in the intensity of the ambient magnetic field from 33–44 to 500 μT enhanced growth inhibition in A. thaliana under blue light, when cryptochromes are… Expand
Blue light-dependent phosphorylations of cryptochromes are affected by magnetic fields in Arabidopsis
Abstract The blue light receptor cryptochrome that could form radical pairs after exposure to blue light was suggested to be a magnetoreceptor based on the proposition that radical pairs wereExpand
The Cryptochrome Blue Light Receptors
TLDR
It is hypothesized that photons excite electrons of the flavin molecule, resulting in redox reaction or circular electron shuttle and conformational changes of the photoreceptors, which alters gene expression at both transcriptional and posttranslational levels and consequently the metabolic and developmental programs of plants. Expand
Cryptochrome-mediated light responses in plants.
TLDR
This chapter will review some aspects of CRY-mediated light responses in plants, including photochemistry and signal transduction mechanism of plant CRYs. Expand
Magnetic field effects in Arabidopsis thaliana cryptochrome-1.
TLDR
A model of the flavin-adenine-dinucleotide-tryptophan chain system that incorporates realistic hyperfine coupling constants and reaction rate constants is presented and calculations show that the radical-pair mechanism in cryptochrome can produce an increase in the protein's signaling activity of approximately 10% for magnetic fields on the order of 5 G, which is consistent with experimental results. Expand
Magnetic sensitivity mediated by the Arabidopsis blue-light receptor cryptochrome occurs during flavin reoxidation in the dark
TLDR
Investigating the response of Arabidopsis cryptochrome-1 in vivo to a static magnetic field using both plant growth and light-dependent phosphorylation as an assay indicates that the magnetically sensitive reaction step in the Cryptochrome photocycle must occur during flavin reoxidation, and likely involves the formation of reactive oxygen species. Expand
A near-null magnetic field affects cryptochrome-related hypocotyl growth and flowering in Arabidopsis
Abstract The blue light receptor, cryptochrome, has been suggested to act as a magnetoreceptor based on the proposition that photochemical reactions are involved in sensing the geomagnetic field. ButExpand
Mechanisms of Cryptochrome-Mediated Photoresponses in Plants.
TLDR
These two mechanisms enable cryptochromes to integrate blue-light signals with other internal and external signals to optimize plant growth and development. Expand
Cellular metabolites modulate in vivo signaling of Arabidopsis cryptochrome-1
TLDR
It is shown that in vivo modulation by metabolites in the cellular environment may play an important role in cryptochrome signaling, and possible effects on the conformation of the C-terminal domain to generate the biologically active conformational state are discussed. Expand
Effect of magnetic fields on cryptochrome-dependent responses in Arabidopsis thaliana
TLDR
The potential importance of this study in the debate on putative effects of extremely low-frequency electromagnetic fields on human health prompted us to subject it to the ‘gold standard’ of independent replication, and in no case were consistent, statistically significant magnetic field responses detected. Expand
Geomagnetic field impacts on cryptochrome and phytochrome signaling.
TLDR
The GMF was found to impact photomorphogenic-promoting gene expression in etiolated seedlings, indicating the existence of a light-independent magnetoreception mechanism, and shows that magnetoreceptor signaling in Arabidopsis, but it does not necessarily depend on light. Expand
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