Plant material and growth
Wild type Col-0 seeds were obtained from the Nottingham Arabidopsis
Stock Centre. Seeds possessing insertions in the gene At5g50950 encoding
cytosolic FUM2 protein (Pracharoenwattana et al. , 2010) were
kindly provided by Professor Steven Smith (University of Tasmania,
Australia). Plants were grown in an SGC120 growth cabinet (Weiss
Technik) with an 8-h photoperiod, temperature of 20°C day/16°C night,
and irradiance of 100 µmol m−2 s−1provided by warm white fluorescent tubes for 8 weeks in 3-inch pots
containing peat-based compost. After 8 weeks, plants had reached growth
stage 1.10 (Boyes et al. , 2001), with more than 10 leaves
> 1 mm and persisted without development of flowers until
10 to 12 weeks. Plants for cold treatment were transferred to a similar
cabinet at 4°C day/night 1 h prior to the start of the photoperiod.
Leaves for metabolite measurements were harvested by flash freezing in
liquid nitrogen under growth conditions.