Wrinkled1 Accelerates Flowering and Regulates Lipid Homeostasis between Oil Accumulation and Membrane Lipid Anabolism in Brassica napus

Abstract

Wrinkled1 (WRI1) belongs to the APETALA2 transcription factor family; it is unique to plants and is a central regulator of oil synthesis in Arabidopsis. The effects of WRI1 on comprehensive lipid metabolism and plant development were unknown, especially in crop plants. This study found that BnWRI1 in Brassica napus accelerated flowering and enhanced oil accumulation in both seeds and leaves without leading to a visible growth inhibition. BnWRI1 decreased storage carbohydrates and increased soluble sugars to facilitate the carbon flux to lipid anabolism. BnWRI1 is localized to the nucleus and directly binds to the AW-box at proximal upstream regions of genes involved in fatty acid (FA) synthesis and lipid assembly. The overexpression (OE) of BnWRI1 resulted in the up-regulation of genes involved in glycolysis, FA synthesis, lipid assembly, and flowering. Lipid profiling revealed increased galactolipids monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), and phosphatidylcholine (PC) in the leaves of OE plants, whereas it exhibited a reduced level of the galactolipids DGDG and MGDG and increased levels of PC, phosphatidylethanolamide, and oil [triacylglycerol (TAG)] in the siliques of OE plants during the early seed development stage. These results suggest that BnWRI1 is important for homeostasis among TAG, membrane lipids and sugars, and thus facilitates flowering and oil accumulation in B. napus.

Ectopic expression of EuWRI1, encoding a transcription factor in E. ulmoides, changes the seeds oil content in transgenic tobacco

“…Our result also showed that expression of EuWRI1 did not affect total protein content in the transgenic tobacco seeds compared with WT. This result was consistent with previous reports that overexpression of WRI1 gene did not affect total protein content in the transgenic plant …”

Selection for a Zinc-Finger Protein Contributes to Seed Oil Increase during Soybean Domestication

“…WRI1 homologs in many plant species, such as ZmWRI1 and BnWRI1, are proved to participate in lipogenesis (Shen et al, 2010;Li et al, 2015). Therefore, we speculate that the up-regulation of Glyma15g34770 (GmWRI1-like1) and Glyma08g24420 (GmWRI1-like2) may consistently enhance seed oil accumulation.…”

Properties and Biotechnological Applications of Acyl‐CoA:diacylglycerol Acyltransferase and Phospholipid:diacylglycerol Acyltransferase from Terrestrial Plants and Microalgae

“…Similar to ABI4 , ABI5 was also shown to synergistically regulate the expression of DGAT1 under stress (Kong et al, ). In addition, overexpression of WRI in B. napus increased the expression of DGAT1 together with GPAT9 and LPAAT2 , although the specific promoter sequence has yet to be identified (Li et al, ). Very recently, the R2R3‐type MYB96 transcription factor was shown to regulate TAG biosynthesis by directly activating the expression of DGAT1 and PDAT1 (Fig.…”

“…Abbreviation: ABI, ABSCISIC ACID INSENSTIVE; DGAT, acyl‐CoA:diacylglycerol acyltransferase; LEC, LEAFY COTYLEDON; MYB96, R2R3‐type MYB96 transcription factor; PDAT, phospholipid:diacyglycerol acyltransferase; and WRI, WRINKLED. This figure was developed based on information from reviews and research articles on transcriptional regulation of DGAT and PDAT (Baud et al, ; Kong et al, ; Lee et al, ; Li et al, ; Santos‐Mendoza et al, ; Wind et al, ; Yang et al, ).…”