Environmental regulation of leaf colour in red 35S:PAP1 Arabidopsis

Examine global gene expression patterns in control and 35S:PAP1 Arabidopsis plants upon environmental perturbation (light and temperature) over the course of the experiments. Red coloured 35S:PAP1, and empty vector control, plants of Arabidopsis thaliana Columbia were grown under room temperature, high light (RTHL, 22°C, 440 µmol m-2 s-1 irradiance) conditions to promote red leaf colouration. The growth conditions were then changed to a high day temperature, low light (HTLL: 30°C day, 150 µmol m-2 s-1 irradiance) stress treatment for six days, during which time the 35S:PAP1 leaves lost much of their red colouration, turning green. The growth conditions were then returned to a low temperature high light (LTHL, 15°C, 62% RH, 440 µmol m-2 s-1 irradiance) regime to restore the red colouration.