Acyl CoA profiles of transgenic plants that accumulate medium-chain

fatty acids indicate inefficient storage lipid synthesis in developing

oilseeds

T.R. Larson; T. Edgell; J. Byrne; K. Dehesh; I.A. Graham

doi:10.1046/j.1365-313X.2002.01440.x

Acyl CoA profiles of transgenic plants that accumulate medium-chain fatty acids indicate inefficient storage lipid synthesis in developing oilseeds

T.R. Larson, T. Edgell, J. Byrne, K. Dehesh, I.A. Graham

CNAP

Research output: Contribution to journal › Article › peer-review

Abstract

Several Brassica napus lines transformed with genes responsible for the synthesis of medium- or long-chain fatty acids were examined to determine limiting factor(s) for the subsequent accumulation of these fatty acids in seed lipids. Examination of a decanoic acid (10:0) accumulating line revealed a disproportionately high concentration of 10:0 CoA during seed development compared to long-chain acyl CoAs isolated from the same tissues, suggesting that poor incorporation of 10:0 CoA into seed lipids limits 10:0 fatty acid accumulation. This relationship was also seen for dodecanoyl (12:0) CoA and fatty acid in a high 12:0 line, but not for octadecanoic (18:0) CoA and fatty acid in a high 18:0 line. Comparison of 10:0 CoA and fatty acid proportions from seeds at different developmental stages for transgenic B. napus and Cuphea hookeriana, the source plant for the medium-chain thioesterase and 3-ketoacyl-ACP synthase transgenes, revealed that C. hookeriana incorporates 10:0 CoA into seed lipids more efficiently than transgenic B. napus. Furthermore, ß-oxidation and glyoxylate cycle activities were not increased above wild type levels during seed development in the 8:0/10:0 line, suggesting that lipid catabolism was not being induced in response to the elevated 10:0 CoA concentrations. Taken together, these data suggest that transgenic plants that are engineered to synthesize medium-chain fatty acids may lack the necessary mechanisms, such as specific acyltransferases, to incorporate these fatty acids efficiently into seed lipids.

Original language	English
Pages (from-to)	519-527
Number of pages	9
Journal	Plant Journal
Volume	32
Issue number	4
DOIs	https://doi.org/10.1046/j.1365-313X.2002.01440.x
Publication status	Published - Nov 2002

Bibliographical note

Open access copy available from the journal web site.

Keywords

acyl CoA
Brassica napus
beta-oxidation
lipid synthesis
medium-chain fatty acids
BINDING PROTEIN
BRASSICA-NAPUS
3-KETOACYL-ACP SYNTHASE
ARABIDOPSIS-THALIANA
DEVELOPING SEEDS
BETA-OXIDATION
LAURATE
TRIACYLGLYCEROL
ACYLTRANSFERASE
BIOSYNTHESIS

Access to Document

10.1046/j.1365-313X.2002.01440.x

http://dx.doi.org/10.1046/j.1365-313X.2002.01440.x

Cite this

@article{54664dd69cfa4788a735d47b86f28b07,

title = "Acyl CoA profiles of transgenic plants that accumulate medium-chain fatty acids indicate inefficient storage lipid synthesis in developing oilseeds",

abstract = "Several Brassica napus lines transformed with genes responsible for the synthesis of medium- or long-chain fatty acids were examined to determine limiting factor(s) for the subsequent accumulation of these fatty acids in seed lipids. Examination of a decanoic acid (10:0) accumulating line revealed a disproportionately high concentration of 10:0 CoA during seed development compared to long-chain acyl CoAs isolated from the same tissues, suggesting that poor incorporation of 10:0 CoA into seed lipids limits 10:0 fatty acid accumulation. This relationship was also seen for dodecanoyl (12:0) CoA and fatty acid in a high 12:0 line, but not for octadecanoic (18:0) CoA and fatty acid in a high 18:0 line. Comparison of 10:0 CoA and fatty acid proportions from seeds at different developmental stages for transgenic B. napus and Cuphea hookeriana, the source plant for the medium-chain thioesterase and 3-ketoacyl-ACP synthase transgenes, revealed that C. hookeriana incorporates 10:0 CoA into seed lipids more efficiently than transgenic B. napus. Furthermore, {\ss}-oxidation and glyoxylate cycle activities were not increased above wild type levels during seed development in the 8:0/10:0 line, suggesting that lipid catabolism was not being induced in response to the elevated 10:0 CoA concentrations. Taken together, these data suggest that transgenic plants that are engineered to synthesize medium-chain fatty acids may lack the necessary mechanisms, such as specific acyltransferases, to incorporate these fatty acids efficiently into seed lipids.",

keywords = "acyl CoA, Brassica napus, beta-oxidation, lipid synthesis, medium-chain fatty acids, BINDING PROTEIN, BRASSICA-NAPUS, 3-KETOACYL-ACP SYNTHASE, ARABIDOPSIS-THALIANA, DEVELOPING SEEDS, BETA-OXIDATION, LAURATE, TRIACYLGLYCEROL, ACYLTRANSFERASE, BIOSYNTHESIS",

author = "T.R. Larson and T. Edgell and J. Byrne and K. Dehesh and I.A. Graham",

note = "Open access copy available from the journal web site.",

year = "2002",

month = nov,

doi = "10.1046/j.1365-313X.2002.01440.x",

language = "English",

volume = "32",

pages = "519--527",

journal = "Plant Journal",

issn = "0960-7412",

publisher = "Wiley-Blackwell",

number = "4",

}

TY - JOUR

T1 - Acyl CoA profiles of transgenic plants that accumulate medium-chain fatty acids indicate inefficient storage lipid synthesis in developing oilseeds

AU - Larson, T.R.

AU - Edgell, T.

AU - Byrne, J.

AU - Dehesh, K.

AU - Graham, I.A.

N1 - Open access copy available from the journal web site.

PY - 2002/11

Y1 - 2002/11

N2 - Several Brassica napus lines transformed with genes responsible for the synthesis of medium- or long-chain fatty acids were examined to determine limiting factor(s) for the subsequent accumulation of these fatty acids in seed lipids. Examination of a decanoic acid (10:0) accumulating line revealed a disproportionately high concentration of 10:0 CoA during seed development compared to long-chain acyl CoAs isolated from the same tissues, suggesting that poor incorporation of 10:0 CoA into seed lipids limits 10:0 fatty acid accumulation. This relationship was also seen for dodecanoyl (12:0) CoA and fatty acid in a high 12:0 line, but not for octadecanoic (18:0) CoA and fatty acid in a high 18:0 line. Comparison of 10:0 CoA and fatty acid proportions from seeds at different developmental stages for transgenic B. napus and Cuphea hookeriana, the source plant for the medium-chain thioesterase and 3-ketoacyl-ACP synthase transgenes, revealed that C. hookeriana incorporates 10:0 CoA into seed lipids more efficiently than transgenic B. napus. Furthermore, ß-oxidation and glyoxylate cycle activities were not increased above wild type levels during seed development in the 8:0/10:0 line, suggesting that lipid catabolism was not being induced in response to the elevated 10:0 CoA concentrations. Taken together, these data suggest that transgenic plants that are engineered to synthesize medium-chain fatty acids may lack the necessary mechanisms, such as specific acyltransferases, to incorporate these fatty acids efficiently into seed lipids.

AB - Several Brassica napus lines transformed with genes responsible for the synthesis of medium- or long-chain fatty acids were examined to determine limiting factor(s) for the subsequent accumulation of these fatty acids in seed lipids. Examination of a decanoic acid (10:0) accumulating line revealed a disproportionately high concentration of 10:0 CoA during seed development compared to long-chain acyl CoAs isolated from the same tissues, suggesting that poor incorporation of 10:0 CoA into seed lipids limits 10:0 fatty acid accumulation. This relationship was also seen for dodecanoyl (12:0) CoA and fatty acid in a high 12:0 line, but not for octadecanoic (18:0) CoA and fatty acid in a high 18:0 line. Comparison of 10:0 CoA and fatty acid proportions from seeds at different developmental stages for transgenic B. napus and Cuphea hookeriana, the source plant for the medium-chain thioesterase and 3-ketoacyl-ACP synthase transgenes, revealed that C. hookeriana incorporates 10:0 CoA into seed lipids more efficiently than transgenic B. napus. Furthermore, ß-oxidation and glyoxylate cycle activities were not increased above wild type levels during seed development in the 8:0/10:0 line, suggesting that lipid catabolism was not being induced in response to the elevated 10:0 CoA concentrations. Taken together, these data suggest that transgenic plants that are engineered to synthesize medium-chain fatty acids may lack the necessary mechanisms, such as specific acyltransferases, to incorporate these fatty acids efficiently into seed lipids.

KW - acyl CoA

KW - Brassica napus

KW - beta-oxidation

KW - lipid synthesis

KW - medium-chain fatty acids

KW - BINDING PROTEIN

KW - BRASSICA-NAPUS

KW - 3-KETOACYL-ACP SYNTHASE

KW - ARABIDOPSIS-THALIANA

KW - DEVELOPING SEEDS

KW - BETA-OXIDATION

KW - LAURATE

KW - TRIACYLGLYCEROL

KW - ACYLTRANSFERASE

KW - BIOSYNTHESIS

U2 - 10.1046/j.1365-313X.2002.01440.x

DO - 10.1046/j.1365-313X.2002.01440.x

M3 - Article

SN - 0960-7412

VL - 32

SP - 519

EP - 527

JO - Plant Journal

JF - Plant Journal

IS - 4

ER -