Open AccessThe Peanut (Arachis hypogaea L.) Gene AhLPAT2 Increases the Lipid Content of Transgenic Arabidopsis Seeds
Author(s) -
Silong Chen,
Yong Lei,
Xiaogang Xu,
Jiaquan Huang,
Huifang Jiang,
Wang Jin,
Zengshu Cheng,
Jianan Zhang,
Yue Song,
Boshou Liao,
Yurong Li
Publication year - 2015
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0136170
Subject(s) - arachis hypogaea , acyltransferase , biology , arabidopsis , silique , lysophosphatidic acid , biochemistry , fatty acid , fatty acid synthesis , phosphatidic acid , genetically modified crops , arachis , transgene , gene , botany , mutant , phospholipid , membrane , receptor
Lysophosphatidic acid acyltransferase (LPAT), which converts lysophosphatidic acid (LPA) to phosphatidic acid (PA), catalyzes the addition of fatty acyl moieties to the sn -2 position of the LPA glycerol backbone in triacylglycerol (TAG) biosynthesis. We recently reported the cloning and temporal-spatial expression of a peanut ( Arachis hypogaea ) AhLPAT2 gene, showing that an increase in AhLPAT2 transcript levels was closely correlated with an increase in seed oil levels. However, the function of the enzyme encoded by the AhLPAT2 gene remains unclear. Here, we report that AhLPAT2 transcript levels were consistently higher in the seeds of a high-oil cultivar than in those of a low-oil cultivar across different seed developmental stages. Seed-specific overexpression of AhLPAT2 in Arabidopsis results in a higher percentage of oil in the seeds and greater-than-average seed weight in the transgenic plants compared with the wild-type plants, leading to a significant increase in total oil yield per plant. The total fatty acid (FA) content and the proportion of unsaturated FAs also increased. In the developing siliques of AhLPAT2 -overexpressing plants, the expression levels of genes encoding crucial enzymes involved in de novo FA synthesis, acetyl-CoA subunit ( AtBCCP2 ) and acyl carrier protein 1 ( AtACP1 ) were elevated. AhLPAT2 overexpression also promoted the expression of several key genes related to TAG assembly, sucrose metabolism, and glycolysis. These results demonstrate that the expression of AhLPAT2 plays an important role in glycerolipid production in peanuts.