Carbon fixation (endogenous sugar) and light-dependent gene expression

Internal sugar and light specific dependent regulation of leaf gene expression was addressed by changing [CO2] to lower than compensation point [CO2] in combination with light or prolonged darkness. Plants were grown on soil in a 12/12 h light/dark rhythm at 20C day and night and under normal [CO2]. 5 weeks after germination, the above-ground rosettes of the non-flowering plants were harvested, 12 plants per sample. Plants were harvested 4hrs after the end of night (i) under low (< 50 ppm) [CO2] and 150 E fluorescent light , (ii) under normal [CO2] and light, and, (iii) under low [CO2] and prolonged darkness. The low [CO2] treatment started 30 min before the end of night and stopped with harvesting.

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