Figure 1.

Change of GIPC and hCer Levels in Arabidopsis rosettes and roots in response to phosphate starvation. A, The level of GIPC in rosettes and roots with and without phosphate. Levels of GIPC are shown relative to the level of GIPC in rosettes during sufficient phosphate (set at 100%). B, Heat map showing the level of GIPC species in rosettes and roots with and without phosphate. Each horizontal colored bar represents the log2 of the concentration (nmol g⁻¹ dry weight) as shown in the color key. C, Levels of hCer in rosettes and roots with and without phosphate. The levels of hCer are shown relative to the level of hCer in rosettes during sufficient phosphate (100%). D, Heat map showing the levels of hCer species in rosettes and roots with and without phosphate. Each horizontal colored bar represents the log2 of the concentration [(nmol g⁻¹ dry weight) × 10] as shown in the color key. Three-day-old seedlings were transferred to a phosphate-sufficient or -deficient half-strength MS medium for 10 days. In (B) and (D), five replicates of rosette and root samples were harvested for lipid analysis by mass spectrometry and the average data of each species were normalized by a log₂ calculation method (n = 5; Szymanski et al., 2014). The heat map was drawn using Heatmap Illustrator (version of HemI 1.0.3.3). *Significant at P < 0.05; **Significant at P < 0.01 compared with the phosphate-sufficient condition in the same tissue, based on Student’s t test (Supplemental Data Set 1). The phosphate treatments, lipid extraction and analysis in (A) and (C) were repeated three times with consistent results, and the results of one representative lipid analysis are shown.