title: Identification of a critical determinant that enables efficient fatty acid synthesis in oleaginous fungi.
abstract: Microorganisms are valuable resources for lipid production. What makes one microbe but not the other able to efficiently synthesize and accumulate lipids is poorly understood. In the present study, global gene expression prior to and after the onset of lipogenesis was determined by transcriptomics using the oleaginous fungus Mortierella alpina as a model system. A core of 23 lipogenesis associated genes was identified and their expression patterns shared a high similarity among oleaginous microbes Chlamydomonas reinhardtii, Mucor circinelloides and Rhizopus oryzae but was dissimilar to the non-oleaginous Aspergillus nidulans. Unexpectedly, Glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (PGD) in the pentose phosphate pathway (PPP) were found to be the NADPH producers responding to lipogenesis in the oleaginous microbes. Their role in lipogenesis was confirmed by a knockdown experiment. Our results demonstrate, for the first time, that the PPP plays a significant role during fungal lipogenesis. Up-regulation of NADPH production by the PPP, especially G6PD, may be one of the critical determinants that enables efficiently fatty acid synthesis in oleaginous microbes.
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China.
authors.forename: Haiqin
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Guangfei
authors.initials: G
authors.lastname: Hao
authors.affiliation: TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457, P. R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China.
authors.forename: Hongchao
authors.initials: H
authors.lastname: Wang
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China [3] Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Zhennan
authors.initials: Z
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Liming
authors.initials: L
authors.lastname: Liu
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: 1] State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, P.R. China [2] The Synergistic Innovation Center for Food Safety and Nutrition, Wuxi 214122, P.R. China [3] Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Yong Q
authors.initials: YQ
authors.lastname: Chen
mesh_terms: D005227:Fatty Acids / Q000096:biosynthesis*; D005658:Fungi / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal
chemical_list: D005227:Fatty Acids