Millar, A. J., Short, S. R., Chua, N. -H. & Kay, S. A. 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: 9.34). 10/1992; 4(9):1075-87. DOI: 10.1105/tpc.4.9.1075
Source: PubMed


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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    • "In contrast to fluorescence, luciferase does not require light irradiation for excitation and is thus neither subject to photobleaching nor phototoxicity. Hence, luciferase is a suitable reporter for long term in vivo measurements that are extensively used to record and monitor circadian clock activity in bacteria, fungi, plants, flies and mammals [3], [6], [7], [8], [9]. "
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    • "To identify factors that confer trans-activation of the AtHAK5 promoter, we constructed a promoter::reporter fusion with the AtHAK5 promoter and a luciferase reporter gene (LUC) that can be monitored using nondestructive imaging (Millar et al., 1992). A stable homozygous AtHAK5pro:LUC reporter line that was responsive to low potassium was transformed with the pDKS 2–7 vector (Turk et al., 2005) to create a population of randomly integrated activation-tagged lines. "
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