Comparative transcriptome analysis at seven time points during Haematococcus pluvialis motile cell growth and astaxanthin accumulation
Comparative transcriptome analysis at seven time points during Haematococcus pluvialis motile cell growth and astaxanthin accumulation
复制标题
雨生红球藻运动细胞生长和虾青素积累过程中七个时间点的比较转录组分析
DOI：
10.1016/j.aquaculture.2018.12.091
复制
发表时间：
2019-03-30
期刊：
影响因子：
4.5
通讯作者：
Liu, Jianguo
中科院分区：
文献类型：
--
作者：
Li, Qianqian;Zhang, Litao;Liu, Jianguo
虽然在雨生红球藻中胁迫诱导的虾青素积累的分子基础已被仔细研究，但虾青素积累的原因，而不是其他类胡萝卜素，迄今尚未得到彻底的研究。为了提高我们对快速生长的营养细胞增殖、中间细胞转化和静止的非运动细胞形成过程中发生的复杂代谢变化，特别是虾青素生物合成的理解，对具有可感知色差的七个指定发育点进行采样，并使用Illumina NextSeq 500测序仪进行测序。比较转录组分析用于鉴定差异表达的基因。采用RT-qPCR实验来验证通过谱分析鉴定的一些重要DEG。在成对比较后，确定了2674个DEG。根据KEGG途径分析，17个与类胡萝卜素生物合成相关的unigene转录活跃。与参与类胡萝卜素合成的13个DEG相比，lut 1、vde、nced和crtR-3等4个unigene在整个过程中表达量较低，未发现差异表达。这可能是导致H.雨生植物在第4阶段，IcyB的上调伴随着IcyE的下调，这似乎是促进β-胡萝卜素而不是δ-胡萝卜素积累的良好策略。Bkt的变化最大，其次是crtR-1和crtR-2。进一步证实BKT和CrtR在胁迫依赖的虾青素合成起始中起重要作用。RT-qPCR结果与转录组学数据一致。
Although the molecular basis of stress-induced astaxanthin accumulation in Haematococcus pluvialis has been closely studied, the reasons for astaxanthin accumulation, rather than other carotenoids, have not been thoroughly investigated to date. With the aim of improving our understanding of the complex metabolic changes, especially astaxanthin biosynthesis, occurring during fast-growing vegetative cell proliferation, transformation of intermediate cells and formation of resting non-motile cells, seven specified developmental points with perceptible color difference were sampled and sequenced using an Illumina NextSeq500 Sequencer. Comparative transcriptome profiling was employed to identify the differentially expressed genes. RT-qPCR experiments were employed to validate some important DEGs identified by the profiling. After pairwise comparisons, 2674 DEGs were identified. Seventeen unigenes related to carotenoid biosynthesis were actively transcribed according to KEGG pathway analysis. Compared with these thirteen DEGs involved in carotenoid synthesis, four unigenes including lut1, vde, nced and crtR-3 had low expression and were not found to be differentially expressed during the whole process. This is probably one of the reasons for astaxanthin accumulation in H. pluvialis. In phase 4, the up-regulation of IcyB was accompanied by the down-regulation of IcyE, which appears to be a good strategy for promoting the accumulation of beta-carotene, rather than delta-carotene. Bkt came into focus for its most extensive change, followed by crtR-1 and crtR-2. BKT and CrtR were further confirmed to play an essential role in the stress-dependent initiation of astaxanthin synthesis. RT-qPCR results were consistent with the transcriptomic data.