Large-scale screening of Arabidopsis circadian clock mutants by a high-throughput real-time bioluminescence monitoring system
Article first published online: 6 AUG 2004
The Plant Journal
Volume 40, Issue 1, pages 1–11, October 2004
How to Cite
Onai, K., Okamoto, K., Nishimoto, H., Morioka, C., Hirano, M., Kami-ike, N. and Ishiura, M. (2004), Large-scale screening of Arabidopsis circadian clock mutants by a high-throughput real-time bioluminescence monitoring system. The Plant Journal, 40: 1–11. doi: 10.1111/j.1365-313X.2004.02191.x
- Issue published online: 6 AUG 2004
- Article first published online: 6 AUG 2004
- Received 21 March 2004; revised 18 May 2004; accepted 28 May 2004.
- circadian rhythm;
- real-time monitoring;
Using a high-throughput real-time bioluminescence monitoring system, we screened large numbers of Arabidopsis thaliana mutants for extensively altered circadian rhythms. We constructed reporter genes by fusing a promoter of an Arabidopsis flowering-time gene – either GIGANTEA (GI) or FLOWERING LOCUS T (FT) – to a modified firefly luciferase gene (LUC+), and we transferred the fusion gene (PGI::LUC+ or PFT::LUC+) into the Arabidopsis genome. After mutagenesis with ethyl methanesulfonate, 50 000 M2 seedlings carrying the PGI::LUC+ and 50 000 carrying PFT::LUC+ were screened their bioluminescence rhythms. We isolated six arrhythmic (AR) mutants and 29 other mutants that showed more than 3 h difference in the period length or phase of rhythms compared with the wild-type strains. The shortest period length was 16 h, the longest 27 h. Five of the six AR mutants carrying PGI::LUC+ showed arrhythmia in bioluminescence rhythms in both constant light and constant dark. These five AR mutants also showed arrhythmia in leaf movement rhythms in constant light. Genetic analysis revealed that each of the five AR mutants carried a recessive mutation in a nuclear gene and the mutations belonged to three complementation groups, and at least one of which was mapped on a novel locus. Our results suggest that the three loci identified here may contain central clock or clock-related genes, at least one of which may be a novel.