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Abstract Plant lipids represent a fascinating field of scientific study, in part due to a stark dichotomy in the limited fatty acid (FA) composition of cellular membrane lipids vs the huge diversity of FAs that can accumulate in triacylglycerols (TAGs), the main component of seed storage oils. With few exceptions, the strict chemical, structural, and biophysical roles imposed on membrane lipids since the dawn of life have constrained their FA composition to predominantly lengths of 16–18 carbons and containing 0–3 methylene-interrupted carbon-carbon double bonds in cis-configuration. However, over 450 “unusual” FA structures can be found in seed oils of different plants, and we are just beginning to understand the metabolic mechanisms required to produce and maintain this dichotomy. Here we review the current state of plant lipid research, specifically addressing the knowledge gaps in membrane and storage lipid synthesis from 3 angles: pathway fluxes including newly discovered TAG remodeling, key acyltransferase substrate selectivities, and the possible roles of “metabolons.” 

Summary Accumulation of triacylglycerols (TAGs) is crucial during various stages of plant development. InArabidopsis, two enzymes share overlapping functions to produce TAGs, namely acyl‐CoA:diacylglycerol acyltransferase 1 (DGAT1) and phospholipid:diacylglycerol acyltransferase 1 (PDAT1). Loss of function of both genes in adgat1‐1/pdat1‐2double mutant is gametophyte lethal. However, the key regulatory elements controlling tissue‐specific expression of either gene has not yet been identified.We transformed adgat1‐1/dgat1‐1//PDAT1/pdat1‐2parent with transgenic constructs containing theArabidopsis DGAT1promoter fused to theAtDGAT1open reading frame either with or without the first intron.Triple homozygous plants were obtained, however, in the absence of theDGAT1first intron anthers fail to fill with pollen, seed yield isc. 10% of wild‐type, seed oil content remains reduced (similar todgat1‐1/dgat1‐1), and non‐Mendelian segregation of thePDAT1/pdat1‐2locus occurs. Whereas plants expressing theAtDGAT1pro:AtDGAT1transgene containing the first intron mostly recover phenotypes to wild‐type.This study establishes that a combination of the promoter and first intron ofAtDGAT1provides the proper context for temporal and tissue‐specific expression ofAtDGAT1in pollen. Furthermore, we discuss possible mechanisms of intron mediated regulation and how regulatory elements can be used as genetic tools to functionally replace TAG biosynthetic enzymes inArabidopsis. 

Abstract FatPlants, an open-access, web-based database, consolidates data, annotations, analysis results, and visualizations of lipid-related genes, proteins, and metabolic pathways in plants. Serving as a minable resource, FatPlants offers a user-friendly interface for facilitating studies into the regulation of plant lipid metabolism and supporting breeding efforts aimed at increasing crop oil content. This web resource, developed using data derived from our own research, curated from public resources, and gleaned from academic literature, comprises information on known fatty-acid-related proteins, genes, and pathways in multiple plants, with an emphasis on Glycine max, Arabidopsis thaliana, and Camelina sativa. Furthermore, the platform includes machine-learning based methods and navigation tools designed to aid in characterizing metabolic pathways and protein interactions. Comprehensive gene and protein information cards, a Basic Local Alignment Search Tool search function, similar structure search capacities from AphaFold, and ChatGPT-based query for protein information are additional features. Database URL: https://www.fatplants.net/