A novel circadian phenotype based on firefly luciferase expression in transgenic plants. Plant Cell 4:1075-1087

Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-6399.
The Plant Cell (Impact Factor: 9.58). 10/1992; 4(9):1075-87. DOI: 10.1105/tpc.4.9.1075
Source: PubMed

ABSTRACT A 320-bp fragment of the Arabidopsis cab2 promoter is sufficient to mediate transcriptional regulation by both phytochrome and the circadian clock. We fused this promoter fragment to the firefly luciferase (Luc) gene to create a real-time reporter for regulated gene expression in intact plants. Cab2::Luc transcript accumulated in the expected patterns and luciferase activity was closely correlated to cab2::Luc mRNA abundance in both etiolated and green seedlings. The concentration of the bulk of luciferase protein did not reflect these patterns but maintained a relatively constant level, implying that a post-translational mechanism(s) leads to the high-amplitude regulation of luciferase activity. We used a low-light video imaging system to establish that luciferase bioluminescence in vivo accurately reports the temporal and spatial regulation of cab2 transcription in single seedlings. The unique qualities of the firefly luciferase system allowed us to monitor regulated gene expression in real time in individual multicellular organisms. This noninvasive marker for temporal regulation at the molecular level constitutes a circadian phenotype, which may be used to isolate mutants in the circadian clock.

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Available from: Steve A Kay, Aug 25, 2015
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    • "We note that the former has been successfully used to measure period, phase and amplitude of 150 accessions in one clock study [85] [102]. However, these methods are not as accurate and precise nor as efficient, as high-throughput assay for measuring rhythms in plant that utilizes clock-controlled promoter luciferase (CCP::LUC) reporter fusions [103]. One caveat with luciferase based assays is that it is a transgenic approach that requires transformation of suitable CCP::LUC constructs. "
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    • "Luc and CCA1:Luc backgrounds. In addition, a transcriptional reporter line, in which the CAB/LHCB promoter drives luciferase expression (PCAB:Luc) was also used to monitor circadian regulation of photosynthetic output pathways, as in plants (Millar et al., 1992 "
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