1. Increase in lysophosphatidate acyltransferase activity in oilseed rape (Brassica napus L.) increases seed triacylglycerol content despite its low intrinsic flux control coefficient
- Author
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Helen Woodfield, Alex Brown, Tony Fawcett, Irina A. Guschina, Ruth Bates, Elizabeth-France Marillia, Stepan Fenyk, John L. Harwood, David C. Taylor, Emma J. Wallington, and David A. Fell
- Subjects
0106 biological sciences ,0301 basic medicine ,DNA, Plant ,Physiology ,Brassica ,Context (language use) ,Plant Science ,01 natural sciences ,Gene Expression Regulation, Enzymologic ,Flux control ,storage oil ,03 medical and health sciences ,Tropaeolum ,Gene Expression Regulation, Plant ,lysophosphatidate acyltransferase ,metabolic control analysis ,Food science ,Triglycerides ,chemistry.chemical_classification ,Full Paper ,biology ,Research ,Acyltransferase activity ,Brassica napus ,Fatty acid ,food and beverages ,Lipid metabolism ,Full Papers ,Plants, Genetically Modified ,biology.organism_classification ,crop improvement ,030104 developmental biology ,chemistry ,Acyltransferase ,TAG ,Seeds ,flux control coefficient ,triacylglycerol ,Flux (metabolism) ,Acyltransferases ,010606 plant biology & botany - Abstract
Summary Lysophosphatidate acyltransferase (LPAAT) catalyses the second step of the Kennedy pathway for triacylglycerol (TAG) synthesis. In this study we expressed Trapaeolum majus LPAAT in Brassica napus (B. napus) cv 12075 to evaluate the effects on lipid synthesis and estimate the flux control coefficient for LPAAT.We estimated the flux control coefficient of LPAAT in a whole plant context by deriving a relationship between it and overall lipid accumulation, given that this process is a exponential.Increasing LPAAT activity resulted in greater TAG accumulation in seeds of between 25% and 29%; altered fatty acid distributions in seed lipids (particularly those of the Kennedy pathway); and a redistribution of label from 14C‐glycerol between phosphoglycerides.Greater LPAAT activity in seeds led to an increase in TAG content despite its low intrinsic flux control coefficient on account of the exponential nature of lipid accumulation that amplifies the effect of the small flux increment achieved by increasing its activity. We have also developed a novel application of metabolic control analysis likely to have broad application as it determines the in planta flux control that a single component has upon accumulation of storage products.
- Published
- 2019