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ARS Home » Midwest Area » Columbia, Missouri » Plant Genetics Research » Research » Publications at this Location » Publication #415810
Research Project: Improving Soybean Seed Composition, Plant Productivity, and Resilience to Climate Change Through Biological Network Modification

Location: Plant Genetics Research

Title: Increasing oil production in leaves by engineering plastidial phospholipase A1

Author
item KIMBERLIN, ATHEN - University Of Missouri
item MAHMUD, SAKIL - University Of Missouri
item HOLTSCLAW, REBEKAH - University Of Missouri
item WALKER, ALEXIE - University Of Missouri
item CONRAD, KRISTINE - University Of Missouri
item MORLEY, STEWART - Danforth Plant Science Center
item WELTI, RUTH - Kansas State University
item Allen, Douglas
item KOO, ABRAHAM - University Of Missouri

Submitted to: Plant Biotechnology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/24/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Engineering of lipids into plant vegetative tissues is a promising approach to produce crops that can be used for biofuel and bioenergy. We describe the production of vegetable oil (i.e., triacylglycerol) in leaves of model and crop species including, Arabidopsis, soybean, and tobacco species by expression of a lipase that cleaves membrane lipids and results in the reallocation of fatty acids to storage lipids. Further characterization of the lines indicates the fatty acid profile in storage oil is consistent with turned over membrane lipids. The studies are important for the development of biofuel crops that produce significant lipid in leaves.

Technical Abstract: Bioengineering efforts to increase oil in non-storage vegetative tissues, which constitute the majority of plant biomass, are promising sustainable sources of renewable fuels and feedstocks. While plants typically do not accumulate significant amounts of triacylglycerol (TAG) in vegetative tissues, the expression of a plastid-localized phospholipase A1 (PLA1) protein, DEFECTIVE IN ANTHER DEHISCENCE1 (DAD1), led to a substantial increase in leaf TAG in Arabidopsis. The inducible DAD1 expression circumvented growth penalties that can be associated with overexpressing lipases and resulted in a rapid burst of TAG within several hours. The increase of TAG was accompanied by the formation of oil bodies in the leaves, petioles, and stems, but not in the roots. Lipid analysis indicated that the increase in TAG was negatively associated with plastidial galactolipid concentration. Thus, the fatty acid (FA) composition of TAG resembled the profile of leaf lipids, rather than seeds and predominantly consisted of 18:3 FAs. Expression of DAD1 in the fad3fad7fad8 mutant, devoid of 18:3 FAs, resulted in comparable TAG accumulation with 18:2 as the major FA constituent, reflecting the flexible in vivo substrate use of DAD1. The transient expression of either DAD1 or NbDAD1 in Nicotiana benthamiana leaves stimulated the accumulation of TAG. Similarly, transgenic soybeans expressing DAD1 exhibited an accumulation of TAG in the leaves, showcasing the biotechnological promise of this technology. In summary, these findings illustrate a novel approach to metabolic engineering for enhanced oil production in vegetative tissues and offer valuable tools for investigating lipid remodeling initiated by plastidial lipases.