Abstract
Lemna plants (duckweeds) have been used for the study of the circadian rhythm and photoperiodic responses. Recently, we have succeeded in monitoring the circadian rhythms of Lemna plants easily by introducing a bioluminescent reporter system transiently with a particle bombardment method. The bioluminescence of plants is measured by a photomultiplier tube, and thus the measured luminescence value is the sum of luminescence of those cells that bioluminescent reporter genes are introduced into. In order to clarify the relationships of circadian rhythms between cells (and the plant body) now we are attempting to establish a monitoring system for circadian rhythms of single cells in living Lemna plants. Lemna plants are very small and flat, and it is easy to observe a whole plant body at high magnification. First, we begin to develop a single-cell monitoring method by applying the bioluminescence reporter system with bright non-circadian reporters. We will report and discuss the conditions of gene transfection, the setup of camera system, imaging data analysis, and growth conditions.
