Cloning and functional analysis of three diacylglycerol acyltransferase genes from peanut (Arachis hypogaea L.)

Xiaoyuan Chi; Ruibo Hu; Xiaowen Zhang; Mingna Chen; Na Chen; Lijuan Pan; Tong Wang; Mian Wang; Zhen Yang; Quanfu Wang; Shanlin Yu

doi:10.1371/journal.pone.0105834

Cloning and functional analysis of three diacylglycerol acyltransferase genes from peanut (Arachis hypogaea L.)

PLoS One. 2014 Sep 2;9(9):e105834. doi: 10.1371/journal.pone.0105834. eCollection 2014.

Authors

Xiaoyuan Chi¹, Ruibo Hu², Xiaowen Zhang³, Mingna Chen⁴, Na Chen⁴, Lijuan Pan⁴, Tong Wang⁴, Mian Wang⁴, Zhen Yang⁴, Quanfu Wang⁵, Shanlin Yu⁴

Affiliations

¹ 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.
² Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences (QIBEBT-CAS), Qingdao, P R China.
³ Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, P R China.
⁴ Shandong Peanut Research Institute, Qingdao, P R China.
⁵ School of Marine and Technology, Harbin Institute of Technology, Weihai, P R China.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acid Sequence
Arachis / enzymology*
Arachis / genetics*
Cloning, Molecular
Diacylglycerol O-Acyltransferase / chemistry
Diacylglycerol O-Acyltransferase / genetics*
Fatty Acids / metabolism
Gene Expression Profiling
Gene Expression Regulation, Plant
Genes, Plant*
Genetic Complementation Test
Lipid Droplets / metabolism
Molecular Sequence Data
Multigene Family
Mutation / genetics
Phylogeny
Protein Structure, Tertiary
Saccharomyces cerevisiae / genetics
Seeds / genetics
Sequence Homology, Amino Acid
Stress, Physiological / genetics
Triglycerides / biosynthesis

Substances

Fatty Acids
Triglycerides
Diacylglycerol O-Acyltransferase

Associated data

GENBANK/KC736067
GENBANK/KC736068
GENBANK/KC736069

Grants and funding

This study was supported by grants from China Agriculture Research System (CARS-14), the National Natural Science Foundation of China (31000728, 31100205, 31200211), the Natural Science Fund of Shangdong Province (ZR2009DQ004, ZR2011CQ036, ZR2012CQ031), Qingdao Municipal Science and Technology Plan Project (11-2-3-26-nsh, 12-1-4-11-(2)-jch), the Fund of Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture (2014010). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.