Fig. 6.

Transcript accumulation of CONSTANS (CO) is induced regardless of when temperature drops occur at night in Arabidopsis thaliana (Columbia-0 (Col-0)); cool temperatures at the beginning of the night induce FLOWERING LOCUS T (FT). (a–c) CO transcript accumulation and (e–g) FT transcript accumulation in response to 4-h periods of 12°C at the beginning of the night from zeitgeber time (ZT) 16 to 20 (a, e early), middle of the night from ZT18 to 22 (b, f mid), and end of the night from ZT20 to 24 (c, g late) in LD. (d) CO transcript accumulation and (h) FT transcript accumulation in LD with constant 12°C conditions (LD12/12°C). All panels show CO and FT transcript accumulation patterns in LD22/22°C and LD22/12°C conditions as references. Data represent means ± SEM derived from at least three biological replicates. Topmost white and black bars designate day and night, respectively. Hashed bars on the top and light blue areas in the graphs represent 4-h cool period (a–c, e–g). Asterisks (a–c, e–g) represent significance (P<0.05) and 95% CI of difference between pair did not contain zero in statistical comparisons between the early, middle, or late night treatments and the LD22/22°C (black) or LD22/12°C controls (red). Asterisks (*) (d, f) represent significance (P<0.05) and 95% CI of difference between pair did not contain zero in statistical comparisons made against the LD22/22°C control.