Carotenoid genes transcriptional regulation for astaxanthin accumulation in fresh water unicellular alga Haematococcus pluvialis by gibberellin A3 (GA3).
The fresh water unicellular alga Haematococcus pluvialis is a promising natural source of astaxanthin. The present study investigated the transcriptional expression of carotenoid genes for astaxanthin accumulation in H. pluvialis using real-time fluorescence quantitative PCR (qRT-PCR). With treatments of 20 and 40 mg/L of gibberllin A3 (GA3), five genes ipi-1, ipi-2, psy, pds and bkt2 were up-regulated with different expression profiles. GA20 (20 mg/L of GA3) treatment had a greater effect on transcriptional expression of bkt2 than on ipi-1 ipi-2, psy and pds (> 4-fold up-regulation). However, GA40 (40 mg/L of GA3) induced more transcriptional expression of ipi-2, psy and bkt2 than both ipi-1 and pds. The expression of lyc, crtR-B and crtO for astaxanthin biosynthesis was not affected by GA3 in H. piuvialis. In the presence of GA3, astaxanthin biosynthesis genes of ipi-1, pds and bkt2 were up-regulated at transcriptional level, psy at post-transcriptional level, whereas ipi-2 was up-regulated at both levels. The study could potentially lead to a scale application of exogenous GA3 in astaxanthin production with H. pluvialis just like GAs perform in increasing crops production and it would provide new insight about the multifunctional roles of carotenogenesis in response to GA3.
Zhengquan
Z
Gao
Chunxiao
C
Meng
Hongzheng
H
Gao
Yan
Y
Li
Xiaowen
X
Zhang
Dong
D
Xu
Shitan
S
Zhou
Banghui
B
Liu
Yuanfeng
Y
Su
Naihao
N
Ye
D002338:Carotenoids / Q000235:genetics*; D004305:Dose-Response Relationship, Drug; D005618:Fresh Water; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D005875:Gibberellins / Q000494:pharmacology*; D010937:Plant Growth Regulators / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects*; D016823:Volvocida / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D024341:Xanthophylls / Q000378:metabolism
D005875:Gibberellins; D010937:Plant Growth Regulators; D024341:Xanthophylls; D002338:Carotenoids; C005948:astaxanthine; C007842:gibberellic acid