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Plant A

Plant B

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This video is a compilation of time lapse frames taken once an hour over a period of five days using video cameras and Kujata software developed by Mark Hyett (University of Virginia; mhyett@std.saic.com) and Steve Kay (Scripps Research Institute). Plant A and Plant B each represent a different Arabidopsis thaliana genotype. Notice that although the plants are of two different genotypes, the seed leaves or cotyledons move in almost perfect synchrony. These seedlings were germinated under a 16:8 LD [16 hours light, 8 hours dark] regimen then transferred to continuous white light at ZT = 3.00 [3 hours after dawn] at three days old. Data collection started at about subjective dawn on Day Four.


Plant A Vertical Data

Plant B Vertical Data

click image above for more detail

Representative Graphs for Plant A and Plant B Type Plants
Vertical Leaf Movement


These graphs represent vertical
Arabidopsis thaliana leaf movement data taken by video cameras and computer software over a period of five days. The data here in red with white fuzzy points are the vertical positions of a single cotyledon, a seed leaf, fit with a representative curve in white by Fast Fourier Transform Non-Linear Least Square (FFT-NLLS) fit analysis. Each peak represents the "up" position of the cotyledon as the underside of the petiole grows more than the upper side. Each trough is the "down" position as the upper side of the petiole grows more than the underside. As the plant itself elongates, the cotyledon is carried upward, and thus the base y position increases with time. FFT-NLLS employs software developed by Martin Straume (University of Virginia; ms3g@virginia.edu) and more fully described in the following publication: Plautz, J.D., Straume, M., Stanewsky, R., Jamison, C.F., Brandes, C., Dowse, H.B., Hall, J.C., and Kay, S.A. (1997). Quantitative analysis of Drosophila period gene transcription in living animals. J. Biol. Rhythms 12, 204-217. Carl Strayer (University of Virginia; cas3s@cms.mail.virginia.edu) wrote a great macro (LMRA) to import the data generated through Mark's software into Marty's FFT-NLLS program.


Graphic representations of circadian [15 - 35 hours] period lengths for individual seed leaf movement for up to 12 plants [= 24 seed leaves] per named genotype, with some having more than one period in circadian range. Each point represents a period length between peaks like those seen in the fit curve shown in the Vertical Leaf Movement Data graphs above versus its relative weakness. The closer the point's relative amplitude [y axis] is to 1, the weaker the rhythm. The mean period length for Plant A type Arabidopsis thaliana plants is not signifcantly different from that of Plant B type plants.


Graphic representations of phase for seed leaf movement circadian rhythms. Each graph includes the phases for up to 12 plants [=24 seed leaves] per named genotype, with some having more than one detectable phase. Each point represents a phase of peaks like those seen in the fit curve shown in the Vertical Leaf Movement Data graphs above versus its relative weakness. The closer the point's relative amplitude [y axis] is to 1, the weaker the rhythm. The mean phase for Plant A type Arabidopsis thaliana plants is not significantly different from that of Plant B type plants.


Leaf Movement References

Acknowledgements

These movie pages were developed by Janet Painter and Bob Gross.

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More Classic Plant Movement Videos (from Roger Hangarter, Indiana University)

Rhythmic Hypocotyl Elongation and Luciferase Videos (from the lab of Andrew Millar, University of Warwick, UK)

Rob McClung's Home Page

 

updated October 17, 2005

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