1
|
Yin X, Guo X, Hu L, Li S, Chen Y, Wang J, Wang RRC, Fan C, Hu Z. Genome-Wide Characterization of DGATs and Their Expression Diversity Analysis in Response to Abiotic Stresses in Brassica napus. PLANTS (BASEL, SWITZERLAND) 2022; 11:1156. [PMID: 35567157 PMCID: PMC9104862 DOI: 10.3390/plants11091156] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 04/22/2022] [Accepted: 04/22/2022] [Indexed: 06/15/2023]
Abstract
Triacylglycerol (TAG) is the most important storage lipid for oil plant seeds. Diacylglycerol acyltransferases (DGATs) are a key group of rate-limiting enzymes in the pathway of TAG biosynthesis. In plants, there are three types of DGATs, namely, DGAT1, DGAT2 and DGAT3. Brassica napus, an allotetraploid plant, is one of the most important oil plants in the world. Previous studies of Brassica napus DGATs (BnaDGATs) have mainly focused on BnaDGAT1s. In this study, four DGAT1s, four DGAT2s and two DGAT3s were identified and cloned from B. napus ZS11. The analyses of sequence identity, chromosomal location and collinearity, phylogenetic tree, exon/intron gene structures, conserved domains and motifs, and transmembrane domain (TMD) revealed that BnaDGAT1, BnaDGAT2 and BnaDGAT3 were derived from three different ancestors and shared little similarity in gene and protein structures. Overexpressing BnaDGATs showed that only four BnaDGAT1s can restore TAG synthesis in yeast H1246 and promote the accumulation of fatty acids in yeast H1246 and INVSc1, suggesting that the three BnaDGAT subfamilies had greater differentiation in function. Transcriptional analysis showed that the expression levels of BnaDGAT1s, BnaDGAT2s and BnaDGAT3s were different during plant development and under different stresses. In addition, analysis of fatty acid contents in roots, stems and leaves under abiotic stresses revealed that P starvation can promote the accumulation of fatty acids, but no obvious relationship was shown between the accumulation of fatty acids with the expression of BnaDGATs under P starvation. This study provides an extensive evaluation of BnaDGATs and a useful foundation for dissecting the functions of BnaDGATs in biochemical and physiological processes.
Collapse
Affiliation(s)
- Xiangzhen Yin
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
- College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xupeng Guo
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
- College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lizong Hu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
- College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- College of Biology and Agriculture, Zhoukou Normal University, Zhoukou 466001, China
| | - Shuangshuang Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
- College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuhong Chen
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
| | - Jingqiao Wang
- Institute of Economical Crops, Yunnan Agricultural Academy, Kunming 650205, China;
| | - Richard R.-C. Wang
- United States Department of Agriculture, Agricultural Research Service, Forage and Range Research Laboratory, Utah State University, Logan, UT 84322-6300, USA;
| | - Chengming Fan
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
| | - Zanmin Hu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; (X.Y.); (X.G.); (L.H.); (S.L.); (Y.C.)
- College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
2
|
Xu Y, Yan F, Zong Y, Li J, Gao H, Liu Y, Wang Y, Zhu Y, Wang Q. Proteomic and lipidomics analyses of high fatty acid AhDGAT3 transgenic soybean reveals the key lipase gene associated with the lipid internal mechanism. Genome 2022; 65:153-164. [PMID: 34995159 DOI: 10.1139/gen-2021-0043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Vegetable oil is one of the most important components of human nutrition. Soybean (Glycine max) is an important oil crop worldwide and contains rich unsaturated fatty acids. Diacylglycerol acyltransferase (DGAT) is a key rate-limiting enzyme in the Kennedy pathway from diacylglycerol (DAG) to triacylglycerol (TAG). In this study, we conducted further research using T3 AhDGAT3 transgenic soybean. A high-performance gas chromatography flame ionization detector showed that oleic acid (18:1) content and total fatty acid content of transgenic soybean were significantly higher than those of the wild type (WT). However, linoleic acid (18:2) was much lower than that in the WT. For further mechanistic studies, 20 differentially expressed proteins (DEPs) and 119 differentially expressed metabolites (DEMs) were identified between WT (JACK) and AhDGAT3 transgenic soybean mature seeds using proteomic and lipidomics analyses. Combined proteomic and lipidomics analyses showed that the upregulation of the key DEP (lipase GDSL domain-containing protein) in lipid transport and metabolic process induced an increase in the total fatty acid and 18:1 composition, but a decrease in the 18:2 composition of fatty acids. Our study provides new insights into the deep study of molecular mechanism underlying the enhancement of fatty acids in transgenic soybeans, especially oleic acid and total fatty acid, which are enhanced by over-expression of AhDGAT3.
Collapse
Affiliation(s)
- Yang Xu
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Fan Yan
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Yu Zong
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Jingwen Li
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Han Gao
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Yajing Liu
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Ying Wang
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Youcheng Zhu
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| | - Qingyu Wang
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
- College of Plant Science, Jilin University, No.5333 Xi'an Road, Changchun City, 130062, China
| |
Collapse
|
3
|
Retraction: Overexpression of Peanut Diacylglycerol Acyltransferase 2 in Escherichia coli. PLoS One 2021; 16:e0252974. [PMID: 34086810 PMCID: PMC8177535 DOI: 10.1371/journal.pone.0252974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
|
4
|
Gao S, Kong Y, Yu J, Miao L, Ji L, Song L, Zeng C. Isolation of axenic cyanobacterium and the promoting effect of associated bacterium on axenic cyanobacterium. BMC Biotechnol 2020; 20:61. [PMID: 33256756 PMCID: PMC7708224 DOI: 10.1186/s12896-020-00656-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 11/16/2020] [Indexed: 11/25/2022] Open
Abstract
Background Harmful cyanobacterial blooms have attracted wide attention all over the world as they cause water quality deterioration and ecosystem health issues. Microcystis aeruginosa associated with a large number of bacteria is one of the most common and widespread bloom-forming cyanobacteria that secret toxins. These associated bacteria are considered to benefit from organic substrates released by the cyanobacterium. In order to avoid the influence of associated heterotrophic bacteria on the target cyanobacteria for physiological and molecular studies, it is urgent to obtain an axenic M. aeruginosa culture and further investigate the specific interaction between the heterotroph and the cyanobacterium. Results A traditional and reliable method based on solid-liquid alternate cultivation was carried out to purify the xenic cyanobacterium M. aeruginosa FACHB-905. On the basis of 16S rDNA gene sequences, two associated bacteria named strain B905–1 and strain B905–2, were identified as Pannonibacter sp. and Chryseobacterium sp. with a 99 and 97% similarity value, respectively. The axenic M. aeruginosa FACHB-905A (Microcystis 905A) was not able to form colonies on BG11 agar medium without the addition of strain B905–1, while it grew well in BG11 liquid medium. Although the presence of B905–1 was not indispensable for the growth of Microcystis 905A, B905–1 had a positive effect on promoting the growth of Microcystis 905A. Conclusions The associated bacteria were eliminated by solid-liquid alternate cultivation method and the axenic Microcystis 905A was successfully purified. The associated bacterium B905–1 has the potentiality to promote the growth of Microcystis 905A. Moreover, the purification technique for cyanobacteria described in this study is potentially applicable to a wider range of unicellular cyanobacteria.
Collapse
Affiliation(s)
- Suqin Gao
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
| | - Yun Kong
- College of Resources and Environment, Yangtze University, Wuhan, 430100, Hubei, China.,Key Laboratory of Water Pollution Control and Environmental Safety of Zhejiang Province, Hangzhou, 310058, Zhejiang, China.,Yixing Academy of Environmental Protection, Nanjing University, Yixing, 214200, Jiangsu, China.,Yixing Urban Supervision & Inspection Administration of Product Quality, National Supervision & Inspection Center of Environmental Protection Equipment Quality (Jiangsu), Yixing, 214205, Jiangsu, China
| | - Jing Yu
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
| | - Lihong Miao
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China.
| | - Lipeng Ji
- College of Resources and Environment, Yangtze University, Wuhan, 430100, Hubei, China
| | - Lirong Song
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
| | - Chi Zeng
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
| |
Collapse
|
5
|
Zhang H, Dong J, Zhao X, Zhang Y, Ren J, Xing L, Jiang C, Wang X, Wang J, Zhao S, Yu H. Research Progress in Membrane Lipid Metabolism and Molecular Mechanism in Peanut Cold Tolerance. FRONTIERS IN PLANT SCIENCE 2019; 10:838. [PMID: 31316538 PMCID: PMC6610330 DOI: 10.3389/fpls.2019.00838] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 06/12/2019] [Indexed: 05/18/2023]
Abstract
Early sowing has been extensively used in high-latitude areas to avoid drought stress during sowing; however, cold damage has become the key limiting factor of early sowing. To relieve cold stress, plants develop a series of physiological and biochemical changes and sophisticated molecular regulatory mechanisms. The biomembrane is the barrier that protects cells from injury as well as the primary place for sensing cold signals. Chilling tolerance is closely related to the composition, structure, and metabolic process of membrane lipids. This review focuses on membrane lipid metabolism and its molecular mechanism, as well as lipid signal transduction in peanut (Arachis hypogaea L.) under cold stress to build a foundation for explicating lipid metabolism regulation patterns and physiological and molecular response mechanisms during cold stress and to promote the genetic improvement of peanut cold tolerance.
Collapse
Affiliation(s)
- He Zhang
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Jiale Dong
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Xinhua Zhao
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Yumei Zhang
- College of Agronomy, Qingdao Agricultural University, Qingdao, China
| | - Jingyao Ren
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Liting Xing
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Chunji Jiang
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Xiaoguang Wang
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Jing Wang
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Shuli Zhao
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
| | - Haiqiu Yu
- Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China
- *Correspondence: Haiqiu Yu,
| |
Collapse
|
6
|
Zheng L, Shockey J, Guo F, Shi L, Li X, Shan L, Wan S, Peng Z. Discovery of a new mechanism for regulation of plant triacylglycerol metabolism: The peanut diacylglycerol acyltransferase-1 gene family transcriptome is highly enriched in alternative splicing variants. JOURNAL OF PLANT PHYSIOLOGY 2017; 219:62-70. [PMID: 29031100 DOI: 10.1016/j.jplph.2017.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/30/2017] [Accepted: 09/30/2017] [Indexed: 06/07/2023]
Abstract
Triacylglycerols (TAGs) are the most important energy storage form in oilseed crops. Diacylglycerol acyltransferase (DGAT) catalyzes the rate-limiting step of the Kennedy pathway of TAG biosynthesis. To date, little is known about the regulation of DGAT activity in peanut (Arachis hypogaea), an agronomically important oilseed crop that is cultivated in many parts of the world. In this study, seven distinct forms of type 1 DGAT (AhDGAT1.1-AhDGAT1.7) were identified, cloned, and characterized. Comparisons of the nucleotide sequences and gene structures revealed many different splicing variants of AhDGAT1, some of which displayed different organ-specific expression patterns. A representative gene (AhDGAT1.1) was transformed into wild-type tobacco and was shown to increase seed fatty acid (FA) content by 14.7%-20.9%. All seven AhDGAT1s were expressed in TAG-deficient Saccharomyces cerevisiae strain H1246; the five longest AhDGAT1 variants generated high levels of acyltransferase activity and complemented the free fatty acid lethality phenotype in this strain. The alternative splicing that gives rise to AhDGAT1.2 and AhDGAT1.4 creates predicted protein C-terminal truncations. The proteins encoded by these two variants were not active and did not complement the fatty acid sensitivity in H1246. These results were verified by visualization of intracellular lipid droplets using Nile Red staining. Collectively, the results presented here represent the first comprehensive analysis of the peanut DGAT1 gene family, which, unlike in other published plant DGAT1 sequences, shows widespread alternative splicing that may affect the expression patterns and enzyme activities of some members of the gene family.
Collapse
Affiliation(s)
- Ling Zheng
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China
| | - Jay Shockey
- United States Department of Agriculture-Agricultural Research Service, Southern Regional Research Center, New Orleans, LA 70124, USA
| | - Feng Guo
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China
| | - Lingmin Shi
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China
| | - Xinguo Li
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China
| | - Lei Shan
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China
| | - Shubo Wan
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China.
| | - Zhenying Peng
- Bio-Tech Research Center, Shandong Academy of Agricultural Science/Shandong Provincial Key Laboratory of Genetic Improvement, Ecology, and Physiology of Crops, Jinan, 250100, China.
| |
Collapse
|
7
|
Zheng L, Shockey J, Bian F, Chen G, Shan L, Li X, Wan S, Peng Z. Variant Amino Acid Residues Alter the Enzyme Activity of Peanut Type 2 Diacylglycerol Acyltransferases. FRONTIERS IN PLANT SCIENCE 2017; 8:1751. [PMID: 29085382 PMCID: PMC5650624 DOI: 10.3389/fpls.2017.01751] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/25/2017] [Indexed: 05/21/2023]
Abstract
Diacylglycerol acyltransferase (DGAT) catalyzes the final step in triacylglycerol (TAG) biosynthesis via the acyl-CoA-dependent acylation of diacylglycerol. This reaction is a major control point in the Kennedy pathway for biosynthesis of TAG, which is the most important form of stored metabolic energy in most oil-producing plants. In this study, Arachis hypogaea type 2 DGAT (AhDGAT2) genes were cloned from the peanut cultivar 'Luhua 14.' Sequence analysis of 11 different peanut cultivars revealed a gene family of 8 peanut DGAT2 genes (designated AhDGAT2a-h). Sequence alignments revealed 21 nucleotide differences between the eight ORFs, but only six differences result in changes to the predicted amino acid (AA) sequences. A representative full-length cDNA clone (AhDGAT2a) was characterized in detail. The biochemical effects of altering the AhDGAT2a sequence to include single variable AA residues were tested by mutagenesis and functional complementation assays in transgenic yeast systems. All six mutant variants retained enzyme activity and produced lipid droplets in vivo. The N6D and A26P mutants also displayed increased enzyme activity and/or total cellular fatty acid (FA) content. N6D mutant mainly increased the content of palmitoleic acid, and A26P mutant mainly increased the content of palmitic acid. The A26P mutant grew well both in the presence of oleic and C18:2, but the other mutants grew better in the presence of C18:2. AhDGAT2 is expressed in all peanut organs analyzed, with high transcript levels in leaves and flowers. These levels are comparable to that found in immature seeds, where DGAT2 expression is most abundant in other plants. Over-expression of AhDGAT2a in tobacco substantially increased the FA content of transformed tobacco seeds. Expression of AhDGAT2a also altered transcription levels of endogenous tobacco lipid metabolic genes in transgenic tobacco, apparently creating a larger carbon 'sink' that supports increased FA levels.
Collapse
Affiliation(s)
- Ling Zheng
- College of Life Science, Shandong University, Jinan, China
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Jay Shockey
- United States Department of Agriculture, Southern Regional Research Center, Agricultural Research Service, New Orleans, LA, United States
| | - Fei Bian
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Gao Chen
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Lei Shan
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Xinguo Li
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Shubo Wan
- College of Life Science, Shandong University, Jinan, China
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- *Correspondence: Zhenying Peng, Shubo Wan,
| | - Zhenying Peng
- College of Life Science, Shandong University, Jinan, China
- Shandong Provincial Key Laboratory of Genetic Improvement, Ecology and Physiology of Crops, Department of Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- *Correspondence: Zhenying Peng, Shubo Wan,
| |
Collapse
|
8
|
Haïli N, Louap J, Canonge M, Jagic F, Louis-Mondésir C, Chardot T, Briozzo P. Expression of Soluble Forms of Yeast Diacylglycerol Acyltransferase 2 That Integrate a Broad Range of Saturated Fatty Acids in Triacylglycerols. PLoS One 2016; 11:e0165431. [PMID: 27780240 PMCID: PMC5079557 DOI: 10.1371/journal.pone.0165431] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/11/2016] [Indexed: 01/28/2023] Open
Abstract
The membrane proteins acyl-CoA:diacylglycerol acyltransferases (DGAT) are essential actors for triglycerides (TG) biosynthesis in eukaryotic organisms. Microbial production of TG is of interest for producing biofuel and value-added novel oils. In the oleaginous yeast Yarrowia lipolytica, Dga1p enzyme from the DGAT2 family plays a major role in TG biosynthesis. Producing recombinant DGAT enzymes pure and catalytically active is difficult, hampering their detailed functional characterization. In this report, we expressed in Escherichia coli and purified two soluble and active forms of Y. lipolytica Dga1p as fusion proteins: the first one lacking the N-terminal hydrophilic segment (Dga1pΔ19), the second one also devoid of the N-terminal putative transmembrane domain (Dga1pΔ85). Most DGAT assays are performed on membrane fractions or microsomes, using radiolabeled substrates. We implemented a fluorescent assay in order to decipher the substrate specificity of purified Dga1p enzymes. Both enzyme versions prefer acyl-CoA saturated substrates to unsaturated ones. Dga1pΔ85 preferentially uses long-chain saturated substrates. Dga1p activities are inhibited by niacin, a specific DGAT2 inhibitor. The N-terminal transmembrane domain appears important, but not essential, for TG biosynthesis. The soluble and active proteins described here could be useful tools for future functional and structural studies in order to better understand and optimize DGAT enzymes for biotechnological applications.
Collapse
Affiliation(s)
- Nawel Haïli
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Julien Louap
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Michel Canonge
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Franjo Jagic
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
| | | | - Thierry Chardot
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Pierre Briozzo
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, Université Paris-Saclay, Versailles, France
- * E-mail:
| |
Collapse
|
9
|
Chi X, Hu R, Zhang X, Chen M, Chen N, Pan L, Wang T, Wang M, Yang Z, Wang Q, Yu S. Cloning and functional analysis of three diacylglycerol acyltransferase genes from peanut (Arachis hypogaea L.). PLoS One 2014; 9:e105834. [PMID: 25181516 PMCID: PMC4152018 DOI: 10.1371/journal.pone.0105834] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 07/25/2014] [Indexed: 11/22/2022] Open
Abstract
Diacylglycerol acyltransferase (DGAT) catalyzes the final and only committed acylation step in the synthesis of triacylglycerols. In this study, three novel AhDGATs genes were identified and isolated from peanut. Quantitative real-time RT-PCR analysis indicated that the AhDGAT1-2 transcript was more abundant in roots, seeds, and cotyledons, whereas the transcript abundances of AhDGAT1-1 and AhDGAT3-3 were higher in flowers than in the other tissues examined. During seed development, transcript levels of AhDGAT1-1 remained relatively low during the initial developmental stage but increased gradually during later stages, peaking at 50 days after pegging (DAP). Levels of AhDGAT1-2 transcripts were higher at 10 and 60 DAPs and much lower during other stages, whereas AhDGAT3-3 showed higher expression levels at 20 and 50 DAPs. In addition, AhDGAT transcripts were differentially expressed following exposure to abiotic stresses or abscisic acid. The activity of the three AhDGAT genes was confirmed by heterologous expression in a Saccharomyces cerevisiae TAG-deficient quadruple mutant. The recombinant yeasts restored lipid body formation and TAG biosynthesis, and preferentially incorporated unsaturated C18 fatty acids into lipids. The present study provides significant information useful in modifying the oil deposition of peanut through molecular breeding.
Collapse
Affiliation(s)
- Xiaoyuan Chi
- Shandong Peanut Research Institute, Qingdao, P R China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, P R China
| | - Ruibo Hu
- Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences (QIBEBT-CAS), Qingdao, P R China
| | - Xiaowen Zhang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, P R China
| | - Mingna Chen
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Na Chen
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Lijuan Pan
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Tong Wang
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Mian Wang
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Zhen Yang
- Shandong Peanut Research Institute, Qingdao, P R China
| | - Quanfu Wang
- School of Marine and Technology, Harbin Institute of Technology, Weihai, P R China
- * E-mail: (QFW); (SLY)
| | - Shanlin Yu
- Shandong Peanut Research Institute, Qingdao, P R China
- * E-mail: (QFW); (SLY)
| |
Collapse
|
10
|
Dey P, Chakraborty M, Kamdar MR, Maiti MK. Functional characterization of two structurally novel diacylglycerol acyltransferase2 isozymes responsible for the enhanced production of stearate-rich storage lipid in Candida tropicalis SY005. PLoS One 2014; 9:e94472. [PMID: 24732323 PMCID: PMC3986092 DOI: 10.1371/journal.pone.0094472] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/16/2014] [Indexed: 12/18/2022] Open
Abstract
Diacylglycerol acyltransferase (DGAT) activity is an essential enzymatic step in the formation of neutral lipid i.e., triacylglycerol in all living cells capable of accumulating storage lipid. Previously, we characterized an oleaginous yeast Candida tropicalis SY005 that yields storage lipid up to 58% under a specific nitrogen-stress condition, when the DGAT-specific transcript is drastically up-regulated. Here we report the identification, differential expression and function of two DGAT2 gene homologues- CtDGAT2a and CtDGAT2b of this C. tropicalis. Two protein isoforms are unique with respect to the presence of five additional stretches of amino acids, besides possessing three highly conserved motifs known in other reported DGAT2 enzymes. Moreover, the CtDGAT2a and CtDGAT2b are characteristically different in amino acid sequences and predicted protein structures. The CtDGAT2b isozyme was found to be catalytically 12.5% more efficient than CtDGAT2a for triacylglycerol production in a heterologous yeast system i.e., Saccharomyces cerevisiae quadruple mutant strain H1246 that is inherently defective in neutral lipid biosynthesis. The CtDGAT2b activity rescued the growth of transformed S. cerevisiae mutant cells, which are usually non-viable in the medium containing free fatty acids by incorporating them into triacylglycerol, and displayed preferential specificity towards saturated acyl species as substrate. Furthermore, we document that the efficiency of triacylglycerol production by CtDGAT2b is differentially affected by deletion, insertion or replacement of amino acids in five regions exclusively present in two CtDGAT2 isozymes. Taken together, our study characterizes two structurally novel DGAT2 isozymes, which are accountable for the enhanced production of storage lipid enriched with saturated fatty acids inherently in C. tropicalis SY005 strain as well as in transformed S. cerevisiae neutral lipid-deficient mutant cells. These two genes certainly will be useful for further investigation on the novel structure-function relationship of DGAT repertoire, and also in metabolic engineering for the enhanced production of lipid feedstock in other organisms.
Collapse
Affiliation(s)
- Prabuddha Dey
- Advanced Laboratory for Plant Genetic Engineering, Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Monami Chakraborty
- Advanced Laboratory for Plant Genetic Engineering, Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Maulik R. Kamdar
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Mrinal K. Maiti
- Advanced Laboratory for Plant Genetic Engineering, Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur, India
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
- * E-mail:
| |
Collapse
|
11
|
Cao H, Shockey JM, Klasson KT, Chapital DC, Mason CB, Scheffler BE. Developmental regulation of diacylglycerol acyltransferase family gene expression in tung tree tissues. PLoS One 2013; 8:e76946. [PMID: 24146944 PMCID: PMC3795650 DOI: 10.1371/journal.pone.0076946] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 08/26/2013] [Indexed: 11/29/2022] Open
Abstract
Diacylglycerol acyltransferases (DGAT) catalyze the final and rate-limiting step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. DGAT genes have been identified in numerous organisms. Multiple isoforms of DGAT are present in eukaryotes. We previously cloned DGAT1 and DGAT2 genes of tung tree (Vernicia fordii), whose novel seed TAGs are useful in a wide range of industrial applications. The objective of this study was to understand the developmental regulation of DGAT family gene expression in tung tree. To this end, we first cloned a tung tree gene encoding DGAT3, a putatively soluble form of DGAT that possesses 11 completely conserved amino acid residues shared among 27 DGAT3s from 19 plant species. Unlike DGAT1 and DGAT2 subfamilies, DGAT3 is absent from animals. We then used TaqMan and SYBR Green quantitative real-time PCR, along with northern and western blotting, to study the expression patterns of the three DGAT genes in tung tree tissues. Expression results demonstrate that 1) all three isoforms of DGAT genes are expressed in developing seeds, leaves and flowers; 2) DGAT2 is the major DGAT mRNA in tung seeds, whose expression profile is well-coordinated with the oil profile in developing tung seeds; and 3) DGAT3 is the major form of DGAT mRNA in tung leaves, flowers and immature seeds prior to active tung oil biosynthesis. These results suggest that DGAT2 is probably the major TAG biosynthetic isoform in tung seeds and that DGAT3 gene likely plays a significant role in TAG metabolism in other tissues. Therefore, DGAT2 should be a primary target for tung oil engineering in transgenic organisms.
Collapse
Affiliation(s)
- Heping Cao
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, Louisiana, United States of America
- * E-mail:
| | - Jay M. Shockey
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, Louisiana, United States of America
| | - K. Thomas Klasson
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, Louisiana, United States of America
| | - Dorselyn C. Chapital
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, Louisiana, United States of America
| | - Catherine B. Mason
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, Louisiana, United States of America
| | - Brian E. Scheffler
- U.S. Department of Agriculture, Agricultural Research Service, Genomics and Bioinformatics Research Unit, Stoneville, Mississippi, United States of America
| |
Collapse
|