Figure 4

Expression of RedCAP and selected members from LHC and LHC-like protein families in diatoms. (A) Cells of P. tricornutum preadapted to LL (45 μmol photons·m⁻²·s⁻¹) with illumination from 8 am to 12 midnight were either kept at LL conditions or transferred to D (no illumination) or ML (750 μmol photons ·m⁻²·s⁻¹ throughout the illumination period) for 33 h and samples were collected every 3 h. Dark and light periods are indicated by grey or white bars, respectively, at the bottom of the expression data. (B) Cells of P. tricornutum preadapted to LL for 6 h (the first 6 h of the regular illumination period) were either kept at LL for additional 6 h or exposed to HL (1,500 to 2,000 μmol photons ·m⁻²·s⁻¹) for 2 h and transferred back to LL for recovery (recov) for 4 h, samples were taken at the times indicated (relative to the transfer into HL). Relative transcript levels were calculated with help of the Relative Expression Software Tool REST [102] using the first sample of each light condition as a calibrator and 18 S rDNA as an endogenous control. The colour code indicates relative gene expression values as indicated by the scale bar on the right. Shown expression levels are average from four independent experiments, grey stars in the coloured boxes mark significant changes compared to the first sample as indicated by the statistical randomisation tests by REST [102].