Fig. 1: The chilling sensitivity of bts-2 is associated with the accumulation of iron.
From: An RNA helicase coordinates with iron signal regulators to alleviate chilling stress in Arabidopsis
a The differentially expressed genes (DEGs) of iron metabolism pathways in plants under 4°C. Col-0 and bts-2 plants were grown at 22 °C for 4 weeks and then were subjected to 4 °C for 24 h. The leaves of four-week-old plants were sampled for transcriptome assays. Two biological replicates were performed. Iron metabolism genes referred to Kim et al.42. b The phenotype of bts-2 plants under chilling stress. Col-0 and bts-2 plants were grown at 26 °C for 3 weeks, then the plants were further grown at 22 °C or 4 °C for 7 days. Arrows indicate the collapsed leaves. Bar = 1 cm. c Iron concentration in Col-0 and bts-2 plants. The plants were grown in soil at 22 °C for 2 weeks and then transferred to 26, 22, and 8 °C for another 2 weeks. Fe concentration is on the dry weight basis, and the leaves of four-week-old plants were sampled for iron elemental analysis. About twenty plants were used for each replicate. Different letters indicate the significant differences based on a two-factor ANOVA with Tukey’s HSD test (P ≤ 0.05, Data are means ± SD, n = 3 biological replicates). d Oversupply of iron increased the chilling sensitivity of bts-2. Col-0 and bts-2 plants were grown on ½ MS at 22 °C for 2 weeks and then transferred to Fe deprivation ½ MS medium (-Fe) supplemented with 10, 100, and 300 μM Fe(II)-EDTA for 1 week at 22 °C and 2 weeks at 8 °C, respectively. 10, 100, and 300 μM Fe correspond to Fe-depleted, Fe-replete, and Fe-excess conditions, respectively. e Chlorophyll concentration of Col-0 and bts-2 seedlings in (d). Six plants for per replicate were collected and used for chlorophyll concentration measurement. Different letters indicate the significant differences based on a two-factor ANOVA with Tukey’s HSD test (P ≤ 0.05, Data are means ± SD, n = 3 biological replicates). Delta values refer to the percentage decline of chlorophyll concentration at 8 °C compared to 22 °C under Fe-replete (100 μM Fe) or Fe-excess (300 μM Fe) conditions. Source data are provided as a Source Data file.
