3.6 DEGs from carotenoid and ABA metabolism
The carotenoid pathway genes, such as phytoene synthase (PSY ),β -carotene hydroxylase (BCH ), and carotenoid β -ring
hydroxylase of cytochrome P450 family (CYP450 -BCH), were
up-regulated in both red and blue light treatments with the exception ofζ -carotene desaturase (ZDS) and lutein deficient 1-like(Lut1) with lower expression levels in blue light treatment
(Figure 6). In addition, the important carotenoid cleavage geneNCED , the key cleavage gene in abscisic acid biosynthesis, was
up-regulated in both the light treatments but higher in red light
treatment (Figure 6). On the other hand, ABA-8’ hydroxylase ,
which is the first step in the ABA catabolism route was highly
up-regulated only under red light treatment but down-regulated (to
-1.88-fold change) in blue light treatment. There were three unigenes
identified as ABA-receptors pyrabactin resistance like gene
(PYL-4,5,8 ) of which two of them (PYL 5,8 ) were
down-regulated to 2-3 folds lower in response to blue light (Figure 6b).
ABA insensitive (ABI5 ) TF was found in similar levels in both the
light treatments.
The related gene expression obtained from qRT-PCR analyses for all the
key anthocyanin and ABA biosynthetic genes discussed above (CHS,
F3’H, F3’5’H, DFR, ANS, UFGT, MYBA1, NCED ) and identified unigenes from
RNA-seq dataset were correlated which showed a higher correlation
R2 values of 0.9 with red vs control and 0.8 with blue
vs control contrasts (Figure S7).