Identification of a pair of phospholipid:diacylglycerol acyltransferases from developing flax (Linum usitatissimum L.) seed catalyzing the selective production of trilinolenin.
J Biol Chem
; 288(33): 24173-88, 2013 Aug 16.
Article
em En
| MEDLINE
| ID: mdl-23824186
ABSTRACT
The oil from flax (Linum usitatissimum L.) has high amounts of α-linolenic acid (ALA; 183(cis)(Δ9,12,15)) and is one of the richest sources of omega-3 polyunsaturated fatty acids (ω-3-PUFAs). To produce â¼57% ALA in triacylglycerol (TAG), it is likely that flax contains enzymes that can efficiently transfer ALA to TAG. To test this hypothesis, we conducted a systematic characterization of TAG-synthesizing enzymes from flax. We identified several genes encoding acyl-CoAdiacylglycerol acyltransferases (DGATs) and phospholipiddiacylglycerol acyltransferases (PDATs) from the flax genome database. Due to recent genome duplication, duplicated gene pairs have been identified for all genes except DGAT2-2. Analysis of gene expression indicated that two DGAT1, two DGAT2, and four PDAT genes were preferentially expressed in flax embryos. Yeast functional analysis showed that DGAT1, DGAT2, and two PDAT enzymes restored TAG synthesis when produced recombinantly in yeast H1246 strain. The activity of particular PDAT enzymes (LuPDAT1 and LuPDAT2) was stimulated by the presence of ALA. Further seed-specific expression of flax genes in Arabidopsis thaliana indicated that DGAT1, PDAT1, and PDAT2 had significant effects on seed oil phenotype. Overall, this study indicated the existence of unique PDAT enzymes from flax that are able to preferentially catalyze the synthesis of TAG containing ALA acyl moieties. The identified LuPDATs may have practical applications for increasing the accumulation of ALA and other polyunsaturated fatty acids in oilseeds for food and industrial applications.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Sementes
/
Triglicerídeos
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Aciltransferases
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Linho
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Biocatálise
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Canadá