Search bioRxiv⌕ Search

bioRxiv · 10.1101/2024.01.23.576967

Genome-Wide Profiling of Soybean WRINKLED1 Transcription Factor Binding Sites Provides Insight into the Regulation of Fatty Acid and Triacylglycerol Biosynthesis Program in Seeds

Abstract

Understanding the regulatory mechanisms controlling storage lipid accumulation will inform strategies to enhance seed oil quality and quantity in crop plants. The WRINKLED1 transcription factor (WRI1 TF) is a central regulator of lipid biosynthesis. We characterized the genome-wide binding profile of soybean (Gm)WRI1 and show that the TF directly regulates genes encoding numerous enzymes and proteins in the fatty acid and triacylglycerol biosynthetic pathways. GmWRI1 binds primarily to regions downstream of target gene transcription start sites. We showed that GmWRI1 bound regions are enriched for the canonical WRI1 DNA binding element, the AW Box (CNTNGNNNNNNNCG), and another DNA motif, the CNC Box (CNCCNCC). Functional assays showed that both DNA elements mediate transcriptional activation by GmWRI1. We also show that GmWRI1 works in concert with other TFs to establish a regulatory state that promotes fatty acid and triacylglycerol biosynthesis. In particular, comparison of genes targeted directly by GmWRI1 and by GmLEC1, a central regulator of the maturation phase of seed development, reveals that the two TFs act in a positive feedback subcircuit to control fatty acid and triacylglycerol biosynthesis. Together, our results provide new insights into the genetic circuitry in which GmWRI1 participates to regulate storage lipid accumulation during seed development. Significance StatementWe report the genome-wide profiling of DNA sequences bound by and the genes directly- regulated by soybean WRINKLED1, a central regulator of storage lipid accumulation in oilseed plants. The information offers new insights into the mechanisms by which WRINKLED1 regulates genes encoding lipid biosynthetic enzymes and establishes a regulatory environment that promotes oil accumulation, and it may aid in the design of strategy to alter storage lipid accumulation in oilseeds.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Jo, L., Pelletier, J., Harada, J. J.. 2024-01-26. Genome-Wide Profiling of Soybean WRINKLED1 Transcription Factor Binding Sites Provides Insight into the Regulation of Fatty Acid and Triacylglycerol Biosynthesis Program in Seeds. https://doi.org/10.1101/2024.01.23.576967

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Combined heat and drought stress alters chromatin accessibility and primes potato abscisic acid biosynthesis

Due to climate change, abiotic stresses get increasingly more frequent, in a combined and recurrent manner in the same growing season. Chromatin accessibility enables efficient responses to combined stress and priming for reoccurring stresses. To study the regulatory basis of priming, we profiled chromatin accessibility and gene expression in leaves of two genetically distinct potato cultivars after prolonged heat, drought, waterlogging, and combined heat and drought. We show that most accessibility changes are stress-specific, however, drought stress elicits a distinct transcriptional response as compared to combined heat and drought stress, with strong chaperone induction and dampened abscisic acid signalling, despite water deficit. A second cycle of combined stress reveals transcriptional memory of abscisic acid biosynthesis gene StNCED3 and its transcriptional activator StWRKY33b, providing a new mechanistic insight of abiotic stress memory in a staple crop important for global food security.

plant biology↗

High-throughput microarray analysis provides new insight into optimising Rubisco yield from diverse plants

Interest in plant-based proteins is increasing due to environmental, ethical, and health considerations. Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), the most abundant protein on Earth, is present in all green leafy biomass and possesses excellent nutritional and functional properties. Despite its potential, Rubisco remains underutilised because extraction methods are often costly, inefficient, and influenced by species-specific differences. Moreover, the impact on Rubisco yield of cell wall-protein interactions remains poorly understood. We applied Microarray Polymer Profiling (MAPP), a high-throughput platform for simultaneous polysaccharide and protein mapping, to characterise diverse leafy biomass sources. This approach revealed interspecies variation and glycan-protein interactions that influence protein extractability and these insights inform biomass selection and optimisation of extraction protocols to improve Rubisco yield. MAPP was also used to evaluate the effects of carbohydrate-active enzymes on Rubisco recovery through targeted cell wall modification.

plant biology↗

Leaf ionomic stability shapes drought adaptation in pearl millet

Pearl millet is a staple cereal of semi-arid West Africa, where early-season water deficit constrains vegetative establishment and yield. While the genetic architecture of the pearl millet foliar ionome has been characterised under well-watered conditions, how this ionome reorganises under drought, and whether this reorganisation has a distinct genetic basis, remains unknown. We profiled the drought-response of 17 foliar elements in 175 diverse pearl millet inbred lines over two seasons in Senegal. The foliar concentration of two co-regulated groups of elements changed reproducibly under early water stress across both years. Leaf ion stability, rather than plasticity, was associated with the maintenance of flowering time and plant biomass, suggesting that drought adaptation in pearl millet relies more on ionomic stability than on adaptive shifts in elemental composition. Among the 17 elements, only potassium showed a significant genotype-by-treatment interaction suggesting that genetic variation contributes to differences in potassium response to drought. Genome-wide association mapping on potassium plasticity in response to drought identified a locus, designated qKP-6, that limits potassium depletion under stress without penalising constitutive potassium levels. This locus represents a candidate region for the genetic control of potassium plasticity under drought. This work provides new insights into the genetic control of mineral nutrition under water deficit in pearl millet, and highlights leaf potassium concentration as a genetically controlled component of drought-responsive ionomic variation with potential implications for drought tolerance.

plant biology↗