Figure 1.
Flowering time of SUC2prom::MYB30 and myb30 mutant plants in LD and SD conditions.
(a)WT and SUC2prom::MYB30 expressing Col plants were grown in LDs (16 h light) and SDs (8 h light) in a temperature controlled climate chamber. The number of rosette and cauline leaves was counted to determine flowering time. Pictures were taken after the WT plants had started to bolt in each condition. Statistical significance was determined using the Student’s t-test (p<0.01). Significant differences are indicated by different letters above the bars, SD and LD treatments are tested as separate experiments. (b) Position of T-DNA insertion lines of myb30. A 400 bp PCR fragment used to detect expression is indicated. (c) Semi-quantitative RT-PCR confirms myb30 mutants as loss-of function alleles. (d) Flowering time of Col, myb30_1, myb30_2 and SUC2prom::MYB30 plants were measured in LD (left) and SD (right) conditions in a temperature controlled climate chamber. Statistical significance was determined using the Student’s t-test by comparing each genotype to the respective Col control (p<0.01). Significant differences are indicated by different letters above the bars. The number of plants for each genotype (n) is indicated below the graph.
Figure 2.
Diurnal expression of MYB30, FT and CO.
(a) Diurnal expression pattern of MYB30 was measured in Col grown in LDs and SDs by RT-qPCR. Total RNA was prepared from 10-day old seedlings sampled every 4 hours (ZT0-ZT24). (b) FT expression was measured comparing WT to SUC2prom::MYB30 expressing Col plants. 10-day-plants in LDs were collected every 4 hours from ZT0-ZT24. (c) CO expression was measured comparing WT to SUC2prom::MYB30 expressing Col plants. 10-day-plants in LDs were collected every 4 hours from ZT0-ZT24. Error bars represent the standard error of three technical replicates relative to the expression of PHOSPHATASE 2A (PP2A). The experiment was repeated three times with similar results.
Figure 3.
Expression of flowering time genes in SUC2 prom::MYB30 expressing plants during development.
Material was collected once per week at ZT16 from WT and SUC2prom::MYB30 expressing Col plants grown in LDs in climate chamber. Samples of 1 week and 2 week old plants were collected from all aerial parts, those of 3–5 weeks from leaves. Expression levels were measured by RT-qPCR for FT (a), TSF (b), FLC (c), and SVP (d). Values are shown as Mean ± SD after normalization of expression with values obtained for PP2A for technical triplicates. A biological replicate of the experiment gave similar results.
Figure 4.
SUC2prom::MYB30 expression accelerates flowering dependent on FT and independent on CO.
Flowering time measurement of Col, SUC2prom::MYB30, ft, SUC2prom::MYB30;ft, co and SUC2prom::MYB30;co under LDs (a) and SDs (b) in the greenhouse. Plants SUC::MYB30;ft and SUC2prom::MYB30;ft;tsf were grown in LDs greenhouse (c). Statistical significance was determined using one way Analysis of Variance (ANOVA) followed by multiple comparison of Holm-Sidak method (p<0.01). Significant differences are indicated by different letters above the bars. The number of plants for each genotype (n) is indicated below the graph.
Figure 5.
Expression of FT and TSF in WT, ft and co plants.
Material from 13-day-seedlings grown on soil in LDs in the greenhouse was collected at ZT16. FT (a) and TSF mRNA (b) levels were determined by RT-qPCR in different genotypes as indicated. Insert in (a) shows values for co and SUC2prom::MYB30;co at a lower scale. Fold-change FT expression in the SUC2prom::MYB30 lines compared to the respective control is indicated above the bar. Values are shown as Mean ± SD after normalization of expression with values obtained for PP2A. Experiments were repeated twice with similar results.
Figure 6.
MYB30 increases 1.0 kb FT promoter activity.
Leaves from Col plants grown in SDs were bombarded with particles carrying 1.0kbFTprom::GreenLUC combined with 35Sprom::MYB30,35Sprom::CO or both as indicated. 35Sprom::RedLUC was included to measure transformation efficiencies. Values are shown as relative GreenLUC compared to RedLUC signals (top panel) after a 16 h–24 h incubation in constant light conditions. Fold-induction over the baseline level obtained for 1.0kbFTprom::GreenLUC alone is indicated in the table below the graph. Values are averages of measurements of five independent leaves from two technical replicates of one bombardment experiment. The experiment was repeated three times with similar results.
Figure 7.
SUC2prom::MYB30 promotes flowering independently of SA and FLC.
(a) Flowering time measurement of Col, NahG, SUC2prom::MYB30 and NahG;SUC2prom::MYB30 under LD conditions. (b) Flowering time measurement of Col, SUC2prom::MYB30, flc and SUC2prom::MYB30;flc under LD conditions. Statistical significance was determent using one way Analysis of Variance (ANOVA) followed by multiple comparison with the Holm-Sidak procedure (p<0.01). Significant differences are indicated by different letters above the bars. The number of plants for each genotype (n) is indicated below the graph.