文献类型：期刊文献

英文题名：Genomic Foundation of Starch-to-Lipid Switch in Oleaginous Chlorella spp.

作者：Fan, Jianhua[1];Ning, Kang[2,3];Zeng, Xiaowei[2,3];Luo, Yuanchan[1];Wang, Dongmei[2,3];Hu, Jianqiang[2,3];Li, Jing[2,3];Xu, Hui[1];Huang, Jianke[1];Wan, Minxi[1];Wang, Weiliang;Zhang, Daojing[1];Shen, Guomin[1];Run, Conglin[1];Liao, Junjie[1];Fang, Lei[1];Huang, Shi[2,3];Jing, Xiaoyan[2,3];Su, Xiaoquan[2,3];Wang, Anhui[2,3];Bai, Lili[4];Hu, Zanmin[4];Xu, Jian[2,3];Li, Yuanguang[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Chinese Acad Sci, Key Lab Biofuels, Single Cell Ctr, Qingdao 266101, Shandong, Peoples R China;[3]Chinese Acad Sci, Qingdao Inst BioEnergy & Bioproc Technol, Shandong Key Lab Energy Genet, Qingdao 266101, Shandong, Peoples R China;[4]Chinese Acad Sci, Inst Genet & Dev Biol, Beijing 100101, Peoples R China

年份：2015

卷号：169

期号：4

起止页码：2444

外文期刊名：PLANT PHYSIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000368472700009)】；

基金：This work was supported by the National Basic Research Program of China (grant nos. 2011CB200904 and 2012CB721101), the National Natural Science Foundation of China (grant nos. 31300295, 31010103907, and 31271410), the Chenguang Program by Shanghai Education Development Foundation and Shanghai Municipal Education Commission, the National Special Fund for State Key Laboratory of Bioreactor Engineering (grant no. 2060204), the National Key Technologies Research and Development Program of China (grant nos. 2011BAD14B02 and 2011BAD23B04), the Fundamental Research Funds for the Central Universities, and the Open Funding Project of the State Key Laboratory of Bioreactor Engineering.

语种：英文

摘要：The ability to rapidly switch the intracellular energy storage form from starch to lipids is an advantageous trait for microalgae feedstock. To probe this mechanism, we sequenced the 56.8-Mbp genome of Chlorella pyrenoidosa FACHB-9, an industrial production strain for protein, starch, and lipids. The genome exhibits positive selection and gene family expansion in lipid and carbohydrate metabolism and genes related to cell cycle and stress response. Moreover, 10 lipid metabolism genes might be originated from bacteria via horizontal gene transfer. Transcriptomic dynamics tracked via messenger RNA sequencing over six time points during metabolic switch from starch-rich heterotrophy to lipid-rich photoautotrophy revealed that under heterotrophy, genes most strongly expressed were from the tricarboxylic acid cycle, respiratory chain, oxidative phosphorylation, gluconeogenesis, glyoxylate cycle, and amino acid metabolisms, whereas those most down-regulated were from fatty acid and oxidative pentose phosphate metabolism. The shift from heterotrophy into photoautotrophy highlights up-regulation of genes from carbon fixation, photosynthesis, fatty acid biosynthesis, the oxidative pentose phosphate pathway, and starch catabolism, which resulted in a marked redirection of metabolism, where the primary carbon source of glycine is no longer supplied to cell building blocks by the tricarboxylic acid cycle and gluconeogenesis, whereas carbon skeletons from photosynthesis and starch degradation may be directly channeled into fatty acid and protein biosynthesis. By establishing the first genetic transformation in industrial oleaginous C. pyrenoidosa, we further showed that overexpression of an NAD(H) kinase from Arabidopsis (Arabidopsis thaliana) increased cellular lipid content by 110.4%, yet without reducing growth rate. These findings provide a foundation for exploiting the metabolic switch in microalgae for improved photosynthetic production of food and fuels.