An Integrated Analysis of Molecular Acclimation to High Light in the Marine Diatom Phaeodactylum tricornutum
Figure 2
Hypothesized carotenoid biosynthetic pathway in P. tricornutum according to Coesel et al. [32].
Colored squares indicate the regulation pattern of genes encoding putative enzymes involved in the synthesis of carotenoids after exposure to HL for 0.5 h, 3 h, 6 h, 12 h, 24 h and 48 h. Squares with a diagonal line inside indicate genes with an expression ratio (log2 transformed) greater than +/−0.5 that are not significantly regulated. The scale on the right represents gene expression ratio values, log2 transformed. The violaxanthin cycle (A) and the diadinoxanthin cycle (B) are boxed. Dashed arrows indicate the hypothetical conversion of violaxanthin to diadinoxanthin and the formation of fucoxanthin from diadinoxanthin, as proposed by Lohr and Wilhelm [52], [53]. The abbreviations used are PSY: phytoene synthase; PDS: phytoene desaturase; ZDS: ζ-carotene desaturase, CRTISO: carotenoid isomerase; crtI: bacterial-like desaturase; LCYB: lycopene β-cyclase; LUT: lutein deficient-like; ZEP: zeaxanthin epoxidase; VDE: violaxanthin de de-epoxidase; VDL: violaxanthin de de-epoxidase-like; VDR: violaxanthin de de-epoxidase related.