title: Transcriptome sequencing and metabolic pathways of astaxanthin accumulated in Haematococcus pluvialis mutant under 15% CO2.
abstract: Transcriptome sequencing and annotation was performed on Haematococcus pluvialis mutant red cells induced with high light under 15% CO2to demonstrate why astaxanthin yield of the mutant was 1.7 times higher than that of a wild strain. It was found that 56% of 1947 differentially expressed genes were upregulated in mutant cells. Most significant differences were found in unigenes related to photosynthesis, carotenoid biosynthesis and fatty acid biosynthesis pathways. The pyruvate kinase increased by 3.5-fold in mutant cells. Thus, more pyruvate, which was beneficial to carotenoids and fatty acid biosynthesis, was generated. Phytoene synthase, zeta-carotene desaturase, lycopene beta-cyclase involved in β-carotene biosynthesis in mutant cells were upregulated by 10.4-, 4.4-, and 5.8-fold, respectively. Beta-carotene 3-hydroxylase catalyzing conversion of β-carotene into astaxanthin was upregulated by 18.4-fold. The fatty acid biosynthesis was promoted because of the upregulation of acetyl-CoA synthetase and acetyl-CoA carboxylase, thus increasing astaxanthin esterification and accumulation in mutant cells.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. Electronic address: juncheng@zju.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Weijuan
authors.initials: W
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Kefa
authors.initials: K
authors.lastname: Cen
mesh_terms: D018533:Biomass; D053898:Biosynthetic Pathways / Q000187:drug effects / Q000235:genetics; D002245:Carbon Dioxide / Q000494:pharmacology*; D002338:Carotenoids / Q000096:biosynthesis; D000460:Chlorophyta / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D005227:Fatty Acids / Q000096:biosynthesis; D005786:Gene Expression Regulation / Q000187:drug effects; D053858:Metabolic Networks and Pathways / Q000187:drug effects / Q000235:genetics*; D058977:Molecular Sequence Annotation; D009154:Mutation / Q000235:genetics*; D011773:Pyruvates / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017423:Sequence Analysis, RNA / Q000379:methods*; D059467:Transcriptome / Q000187:drug effects / Q000235:genetics; D024341:Xanthophylls / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D011773:Pyruvates; D012333:RNA, Messenger; D024341:Xanthophylls; D002245:Carbon Dioxide; D002338:Carotenoids; C005948:astaxanthine
keywords: Astaxanthin; Haematococcus pluvialis; Metabolic pathways; Mutant cells; Transcriptome sequencing