文献类型：期刊文献

英文题名：Overexpression of the soybean transcription factor GmDof4 significantly enhances the lipid content of Chlorella ellipsoidea

作者：Zhang, Jianhui[1];Hao, Qiang[1,2];Bai, Lili[1];Xu, Jin[3];Yin, Weibo[1];Song, Liying[1];Xu, Ling[1];Guo, Xuejie[1];Fan, Chengming[1];Chen, Yuhong[1];Ruan, Jue[3];Hao, Shanting[1];Li, Yuanguang[4];Wang, Richard R-C[5];Hu, Zanmin[1]

机构：[1]Chinese Acad Sci, Inst Genet & Dev Biol, Beijing 100101, Peoples R China;[2]Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China;[3]Chinese Acad Sci, Beijing Inst Genom, Beijing 100029, Peoples R China;[4]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[5]Utah State Univ, USDA ARS, FRRL, Logan, UT 84322 USA

年份：2014

卷号：7

期号：1

外文期刊名：BIOTECHNOLOGY FOR BIOFUELS

收录：;EI(收录号：20144300125181);WOS:【SCI-EXPANDED(收录号:WOS:000341391200001)】；

基金：This research was supported by a project (grant number: 2011CB200902) from the Ministry of Science and Technology of China, a project (grant number: 2011ZX08009-003-004) from the Ministry of Agriculture of China for transgenic research and projects (grant numbers: 21306222 and 21076080) from the National Natural Science Foundation of China.

语种：英文

外文关键词：Microalgae; Chlorella ellipsoidea; Transcription factor; Lipid accumulation; RNA-seq; Acetyl-coenzyme A carboxylase

摘要：Background: The lipid content of microalgae is regarded as an important indicator for biodiesel. Many attempts have been made to increase the lipid content of microalgae through biochemical and genetic engineering. Significant lipid accumulation in microalgae has been achieved using biochemical engineering, such as nitrogen starvation, but the cell growth was severely limited. However, enrichment of lipid content in microalgae by genetic engineering is anticipated. In this study, GmDof4 from soybean (Glycine max), a transcription factor affecting the lipid content in Arabidopsis, was transferred into Chlorella ellipsoidea. We then investigated the molecular mechanism underlying the enhancement of the lipid content of transformed C. ellipsoidea. Results: We constructed a plant expression vector, pGmDof4, and transformed GmDof4 into C. ellipsoidea by electroporation. The resulting expression of GmDof4 significantly enhanced the lipid content by 46.4 to 52.9%, but did not affect the growth rate of the host cells under mixotrophic culture conditions. Transcriptome profiles indicated that 1,076 transcripts were differentially regulated: of these, 754 genes were significantly upregulated and 322 genes were significantly downregulated in the transgenic strains under mixotrophic culture conditions. There are 22 significantly regulated genes (vertical bar log(2) ratio vertical bar > 1) involved in lipid and fatty acid metabolism. Quantitative real-time PCR and an enzyme activity assay revealed that GmDof4 significantly up-regulated the gene expression and enzyme activity of acetyl-coenzyme A carboxylase, a key enzyme for fatty acid synthesis, in transgenic C. ellipsoidea cells. Conclusions: The hetero-expression of a transcription factor GmDof4 gene from soybean can significantly increase the lipid content but not affect the growth rate of C. ellipsoidea under mixotrophic culture conditions. The increase in lipid content could be attributed to the large number of genes with regulated expression. In particular, the acetyl-coenzyme A carboxylase gene expression and enzyme activity were significantly upregulated in the transgenic cells. Our research provides a new way to increase the lipid content of microalgae by introducing a specific transcription factor to microalgae strains that can be used for the biofuel and food industries.