Fig. 4.

CsTOC1 and CsLHY gene expression rhythms in chestnut stems from 16- to 24-week-old seedlings exposed to continuous cold treatment (4°C). Seedlings were grown at LD [16 h light/8 h dark (16:8)] and 22°C and subsequently transferred to 4°C for 52 h. Plants were transferred either in the morning (3 h after the lights were turned on), when LHY mRNA levels are high (A) or at dusk (1 h before lights went off), when TOC1 mRNA levels are high (B). Samples were collected at 3-h intervals. Each experiment was performed at least twice with similar results; one representative data set is shown. The quantification was as described in the legend of Fig. 1.