Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Phytochrome A is an irradiance-dependent red light sensor.

Keara A Franklin1, Trudie Allen, Garry C Whitelam

  • 1Department of Biology, University of Leicester, Leicester LE1 7RH, UK. kaf5@le.ac.uk

The Plant Journal : for Cell and Molecular Biology
|March 10, 2007
PubMed
Summary

Phytochromes, plant light sensors, show surprising activity in red light at high intensities. Phytochrome A (phyA) functions effectively even in bright light, regulating plant growth and development.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Addressing Vitamin B<sub>12</sub> deficiency through aeroponic fortification of a salad crop (Pisum sativum).

Communications biology·2026
Same author

Integration of light quality signals regulates ABA abundance and stomatal movements during seedling establishment.

The New phytologist·2025
Same author

UV RESISTANCE LOCUS 8 signalling enhances photosynthetic resilience to herbicide-induced damage in Arabidopsis thaliana.

The New phytologist·2025
Same author

Molecular heaters: a green route to boosting crop yields?

Physical chemistry chemical physics : PCCP·2025
Same author

25 Years of thermomorphogenesis research: milestones and perspectives.

Trends in plant science·2023
Same author

ELONGATED HYPOCOTYL5 (HY5) and HY5 HOMOLOGUE (HYH) maintain shade avoidance suppression in UV-B.

The Plant journal : for cell and molecular biology·2023

Area of Science:

  • Plant biology
  • Photomorphogenesis
  • Molecular genetics

Background:

  • Plants use phytochromes to sense red (R) and far-red (FR) light.
  • Arabidopsis thaliana has five phytochromes (phyA-phyE).
  • Phytochrome A (phyA) degrades rapidly in light, accumulating in dark-grown seedlings and primarily acting as an FR sensor.

Purpose of the Study:

  • To investigate phyA activity under high R photon irradiances.
  • To understand the role of phytochromes in plant architecture regulation at different light intensities.
  • To explore the mechanisms behind phyA's light response.

Main Methods:

  • Experiments using Arabidopsis thaliana mutants with altered phytochrome genes.
  • Analysis of plant de-etiolation and survival under varying R light conditions.

Related Experiment Videos

  • Observation of phyA protein stability and localization using transgenic lines (phyA:YFP).

    • Main Results:

    • PhyA exhibits significant activity in high R light (>160 micromol m(-2) sec(-1)).
    • Phytochromes A, B, and D redundantly regulate plant architecture under high R light.
    • Quadruple phyBphyCphyDphyE mutants with only phyA survived and de-etiolated in R light.
    • High R light irradiance reduces phyA degradation and enhances nuclear localization, suggesting photoprotection.

    Conclusions:

    • PhyA functions as an effective irradiance sensor across a wider range of light conditions than previously thought.
    • PhyA's activity in high R light contributes to regulating growth and development in daylight-grown plants.
    • Irradiance-dependent photoprotection of nuclear phyA explains its enhanced activity in high R light.