Metabolic engineering of soybean affords improved phytosterol seed traits

摘要: Different combinations of three rate-limiting enzymes in phytosterol biosynthesis, the Arabidopsis thaliana hydroxyl methylglutaryl CoA1 (HMGR1) catalytic subunit linked to either constitutive or seed-specific β-conglycinin promoter, and Glycine max sterol methyltransferase1 (SMT1) methyltransferase2-2 (SMT2-2) genes, under control Glycinin-1 Beta-phaseolin promoters, respectively, were engineered soybean plants. Mature seeds transgenic plants displayed modest increases total content, which points towards a tight biosynthesis. However, contrast wild-type that accumulated about 35% form intermediates, driven by metabolic flux was directed Δ(5) -24-alkyl formation (99% sterol). The effect end-product (sitosterol, campesterol, stigmasterol) over-production resulted an approximately 30% increase overall sitosterol synthesis, desirable trait for oilseeds human health. In contradistinction, increased accumulation cycloartenol 24(28)-methylencylartanol (55% sterol) detected harbouring t-HMGR1 gene, consistent with previous studies. Our results support possibility family pathway is differentially regulated leaves seeds.