Plant Physiology Preview Published on March 23, 2007; 10.1104/pp.107.096206
Received January 19, 2007
Accepted March 16, 2007
ELF4 Is Required for Oscillatory Properties of the Circadian Clock
Harriet G. McWatters , Elsebeth Kolmos , Anthony Hall , Mark R. Doyle , Richard M. Amasino , Péter Gyula , Ferenc Nagy , Andrew J. Millar , and Seth J. Davis *
Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom; Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Koeln, Germany; School of Biological Sciences, University of Liverpool, Liverpool L69 7ZB, United Kingdom; Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA; Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, H-6726 Szeged, Hungary; Institute of Molecular Plant Sciences, University of Edinburgh, Edinburgh EH9 3JH, United Kingdom
* Corresponding author; email: davis{at}mpiz-koeln.mpg.de.
Circadian clocks are required to coordinate metabolism and physiology with daily changes in the environment. Such clocks have several distinctive features including a free-running rhythm of approximately 24 hours and the ability to entrain to both light or temperature cycles (zeitgebers). We have previously characterized the ELF4 locus of Arabidopsis thaliana as being important for robust rhythms. Here it is shown that ELF4 is necessary for at least two core-clock functions: entrainment to an environmental cycle, and rhythm sustainability under constant conditions. We show that elf4 demonstrates clock-input defects in light responsiveness and in circadian gating. Rhythmicity in elf4 could be driven by an environmental cycle but an increased sensitivity to light means the circadian system of elf4 plants does not entrain normally. Expression of putative core-clock genes and outputs were characterized in various ELF4 backgrounds to establish the molecular network of action. ELF4 was found to be intimately associated with the CCA1/LHY-TOC1 feedback loop, as under free-run, ELF4 is required to regulate the expression of CCA1 and TOC1, and further, elf4 is locked in the evening phase of this feedback loop. ELF4 therefore can be considered a component of the central CCA1/LHY-TOC1 feedback loop in the plant circadian clock.
This article has been cited by other articles:

|
 |

|
 |
 
J.-F. Wu, Y. Wang, and S.-H. Wu
Two New Clock Proteins, LWD1 and LWD2, Regulate Arabidopsis Photoperiodic Flowering
Plant Physiology,
October 1, 2008;
148(2):
948 - 959.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Compiled by, F. Tooke, T. Chiurugwi, and N. Battey
Flowering Newsletter bibliography for 2007
J. Exp. Bot.,
July 18, 2008;
(2008)
ern109v1.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. A. Salome, Q. Xie, and C. R. McClung
Circadian Timekeeping during Early Arabidopsis Development
Plant Physiology,
July 1, 2008;
147(3):
1110 - 1125.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Serikawa, K. Miwa, T. Kondo, and T. Oyama
Functional Conservation of Clock-Related Genes in Flowering Plants: Overexpression and RNA Interference Analyses of the Circadian Rhythm in the Monocotyledon Lemna gibba
Plant Physiology,
April 1, 2008;
146(4):
1952 - 1963.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Yakir, D. Hilman, M. Hassidim, and R. M. Green
CIRCADIAN CLOCK ASSOCIATED1 Transcript Stability and the Entrainment of the Circadian Clock in Arabidopsis
Plant Physiology,
November 1, 2007;
145(3):
925 - 932.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. E. Somers, S. Fujiwara, W.-Y. Kim, and S.-S. Suh
Posttranslational Photomodulation of Circadian Amplitude
Cold Spring Harb Symp Quant Biol,
January 1, 2007;
72(0):
193 - 200.
[Abstract]
[PDF]
|
 |
|
|
|