Related Experiment Video
Updated: Jun 27, 2026
07:42
Rapid Analysis of Circadian Phenotypes in Arabidopsis Protoplasts Transfected with a Luminescent Clock Reporter
Published on: September 17, 2016
COP1 and ELF3 control circadian function and photoperiodic flowering by regulating GI stability
Jae-Woong Yu1, Vicente Rubio, Na-Yeoun Lee
1Department of Plant Science and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
Molecular Cell
|December 9, 2008
Summary
Plant cryptochromes (CRY2) sense day length, signaling flowering time. We found COP1 and ELF3 mediate this by targeting GI for degradation, linking light input to the plant circadian clock.
Area of Science:
- Plant biology
- Molecular genetics
- Circadian rhythms
Background:
- Plants use seasonal day length changes to time developmental processes like flowering.
- Cryptochromes (CRYs), COP1, ELF3, and GI are known regulators, but their precise interactions in photoperiod sensing are unclear.
Purpose of the Study:
- To elucidate the regulatory link between CRY2, COP1, ELF3, and GI in photoperiodic flowering.
- To understand how light signals are transmitted to the circadian clock.
Main Methods:
- In vivo interaction studies (co-immunoprecipitation).
- Analysis of GI protein levels in planta.
- Investigating the effects of COP1 and ELF3 mutations on GI cyclic accumulation.
Main Results:
- COP1 and ELF3 interact in vivo.
- ELF3 facilitates COP1-GI interaction, leading to GI degradation.
- Mutations in COP1 or ELF3 disrupt the normal daily accumulation pattern of GI.
Conclusions:
- ELF3 acts as a crucial adaptor protein, linking CRY2-mediated light perception to COP1.
- COP1, with ELF3's help, destabilizes GI, thereby modulating light input to the circadian clock.
- This mechanism provides a direct link between photoperception and the circadian regulation of flowering time.
Related Concept Videos
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:45Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
01:25Cell Signaling in Plants
Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...
02:00Photoreceptors and Plant Responses to Light
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.