SDtoLD 260410

Property Value
BioDare ID 13982031569136
Author Laura Dixon
Institution University of Edinburgh
License CC_BY

Description

pTOC plate 0683 pCAB plate0684 LHY plate 0685 control plate 0686 TOC plate0687 pLHY plate 0688

Purpose

Re-entrainment dynamics during the transition between light:dark cycles with different photoperiods, comparing Arabidopsis thaliana and Ostreococcus tauri. This expt in O. tauri compares transcriptional LUC fusions to TOC1, CAB, and LHY promoters with translational fusions to LHY and TOC promoter + protein. Each marker is on a separate plate to avoid plate-position effects.

Comments

Several controls are relevant, from parallel experiments in adjacent weeks. Data displayed in BioDare are means of 8 cultures in a 96-well plate column, where data from each culture was normalised to its mean before averaging. 6 such columns were measured for each marker (each marker has its own plate). Raw data are shown in the 'normalised' files. Aggregated data in the 'summary.xls' file. NB each plate is counted in sequence, so necessarily at a different time. The four LHY/TOC1 markers are counted within 0.5h, in a total cycle time of 0.707h. For display in BioDare, the times are shown for the middle plate, TOC, but the separate files have the original, separate times. The peak analysis in the publication used the averages for each column.

Sample preparation

Cultures were in alternate columns of the 96-well plates (i.e. columns 1, 3, 5, ... 11) to avoid light crosstalk. This also speeds up plate reading in this two-PMT instrument, which reads columns 1 and 7 together, then skips 2 and 8, etc. The artificial seawater was refreshed and luciferin was applied 24 h before assays started.

Measurement

Protocol

Luciferase luminescence (Top count1)

Control plate shows background <150 cps in L, <30cps in D, insignificant, so no background subtracted.

Experimental conditions

8L:16D

Growth on Artificial Sea Water (ASW) with Keller supplements, plus antibiotics for 7.0 days (8L:16D). White fluorescent tubes filtered with one layer of Ocean Blue gel filter. NB fluence rate was 10 micromol/m2/s. Earlier papers stated 20, this was incorrect.

Light

Type Duration (days) Cycle (h) Start Duration Spectrum Source Intensity
diurnal light 7 24 0:00 8:00 white tube 10

Temperature

Type Duration (days) Cycle (h) Base (°C) Warm (°C) Warm start Warm duration
constant temperature 7 24 20 -- -- --

SD to LD

Growth on Artificial Sea Water (ASW) with Keller supplements, plus antibiotics for 7.0 days (SD to LD). In the stacker of the TopCount with red and blue LEDs

Light

Type Duration (days) Cycle (h) Start Duration Spectrum Source Intensity
diurnal light 2 24 0:00 8:00 red LED 5
diurnal light 5 24 0:00 16:00 red LED 5
diurnal light 2 24 0:00 8:00 blue LED 5
diurnal light 5 24 0:00 16:00 blue LED 5

Temperature

Type Duration (days) Cycle (h) Base (°C) Warm (°C) Warm start Warm duration
constant temperature 7 24 20 -- -- --

Files