Project description:Loss of the seed-specific WRKY transcription factor WRKY43 confers enhanced tolerance towards high salt, high osmolarity and low temperature with respect to seed germination. wrky43 loss of function lines display increased inhibition of seed germination in response to exogenous ABA, while WRKY43 overexpression lines are more tolerant towards exogenous ABA. The opposing effect of the wrky43 mutant on salt and ABA tolerance is reminiscent of fatty acid desaturase mutants. Loss of WRKY43 enhances polyunsaturated fatty acid content, particularly 18:2 and 18:3 in TAGs and Phospholipids. Gene chip arrays show that ABA-induced regulation of FUSCA3, ZAT10 and seed storage proteins are absent in the wrky43 mutant. Promoter-Luciferase studies confirm direct regulation of ZAT10 by WRKY43 and suggest indirect regulation of FUS3 and SSPs. In summary WRKY43 acts as a positive regulator of ABA-dependent gene regulation and of fatty acid desaturation that finally results in enhanced tolerance to abiotic stress. 2 biological replicates of Arabidopsis thaliana Ler-0 wildtype and wrky43 muatnt seeds were compared after incubation in liquid 0.5 MS media with 2 µM ABA for 4 days
Project description:Loss of the seed-specific WRKY transcription factor WRKY43 confers enhanced tolerance towards high salt, high osmolarity and low temperature with respect to seed germination. wrky43 loss of function lines display increased inhibition of seed germination in response to exogenous ABA, while WRKY43 overexpression lines are more tolerant towards exogenous ABA. The opposing effect of the wrky43 mutant on salt and ABA tolerance is reminiscent of fatty acid desaturase mutants. Loss of WRKY43 enhances polyunsaturated fatty acid content, particularly 18:2 and 18:3 in TAGs and Phospholipids. Gene chip arrays show that ABA-induced regulation of FUSCA3, ZAT10 and seed storage proteins are absent in the wrky43 mutant. Promoter-Luciferase studies confirm direct regulation of ZAT10 by WRKY43 and suggest indirect regulation of FUS3 and SSPs. In summary WRKY43 acts as a positive regulator of ABA-dependent gene regulation and of fatty acid desaturation that finally results in enhanced tolerance to abiotic stress.
Project description:Arabidopsis seeds expressing the castor fatty acid hydroxylase accumulate hydroxylated fatty acids up to 17% of total fatty acids in seed triacylglycerols, however total seed oil is also reduced up to 50%. Investigations into the cause of the reduced oil phenotype through in vivo [14C]acteate and [3H]2O metabolic labeling of developing seeds surprisingly revealed that the rate of de novo fatty acid synthesis within the transgenic seeds was approximately half that of control seeds. Addition of castor phospholipid:diacylglycerol acyltransferase (PDAT) increased hydroxylated fatty acid content of the seed oil, increased the rate of fatty acid synthesis, and mostly restored seed oil levels. RNAseq analysis indicated no changes in expression of fatty acid synthesis genes in hydroxylase-expressing plants. Transcript profiles of Arabidopsis developing seeds of three lines, at three stages of development were generated by deep sequencing, in triplicate, using Illumina.
Project description:Arabidopsis seeds expressing the castor fatty acid hydroxylase accumulate hydroxylated fatty acids up to 17% of total fatty acids in seed triacylglycerols, however total seed oil is also reduced up to 50%. Investigations into the cause of the reduced oil phenotype through in vivo [14C]acteate and [3H]2O metabolic labeling of developing seeds surprisingly revealed that the rate of de novo fatty acid synthesis within the transgenic seeds was approximately half that of control seeds. Addition of castor phospholipid:diacylglycerol acyltransferase (PDAT) increased hydroxylated fatty acid content of the seed oil, increased the rate of fatty acid synthesis, and mostly restored seed oil levels. RNAseq analysis indicated no changes in expression of fatty acid synthesis genes in hydroxylase-expressing plants.
Project description:We describe the transcriptional profiles upon 1 mM linolenic acid (Ln) treatment in Arabidopsis cell suspension cultures. Ln is an important fatty acid in plant. We found that Ln treatment induced the expression of 533 genes and repressed the expression of 2501 gene. GO analysis indicated that most of those genes related to Reactive Oxygen Species signaling, abiotic and biotic stress responses, and/or Jasmonic Acid biosynthesis and signaling. This study provides basic information on how Ln regulates the gene expression and fulfils its role in abiotic and biotic stresses.
Project description:Compared to ordinary rapeseed, high-oleic acid rapeseed has higher levels of monounsaturated fatty acids and lower levels of saturated fatty acid and polyunsaturated fatty acids, and thus is of high nutritional and health value. In addition, high-oleic acid rapeseed oil imparts cardiovascular protective effects. Based on these properties, high-oleic acid oil crops have been extensively investigated and cultivated. In this study, we employed a microarray analysis with high oleic acid line and low oleic acid line from the developing seeds (27 days after flowering) of Brassica napus.
Project description:Mature seeds of Arabidopsis thaliana are desiccation tolerant, but they lose DT while progressing to germination. Yet, there is a small developmental window during which DT can be rescued by treatment with abscisic acid (ABA). We used a time-series of microarrays to gain temporal resolution and identify relevant genes in the re-establishment of desiccation tolerance with ABA.