WRKY43 regulates polyunsaturated fatty acid content and abiotic stress tolerance of Arabidopsis seeds
Ontology highlight
ABSTRACT: 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:A case of transcriptional gene silencing, originally observed in tetraploid Arabidopsis plants, created an epiallele resistant to many mutations or inhibitor treatments that activate other suppressed genes. This raised the question about the molecular basis of this extreme stability. A combination of forward and reverse genetics, transcriptome profiling and drug application provides evidence for a double safeguard system that is only alleviated upon the simultaneous removal of both DNA methylation and histone methylation by loss of DDM1 or HOG1 acitivity. Three biological replicates per line are provided. C2S1 = Wt line; hog1-7=774; ddm1-12=1135
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 seedlings, of both wild-type and an ARF7/ARF19 double knockout mutant, were grown to 7 days post-germination. The roots were then dissected into 5 developmental zones, the meristem, early elongation zone, late elongation zone, mature root and lateral root zone. The sections then underwent transcriptional profiling to identify processes and regulatory events specific and in common to the zones.
Project description:Here we compare transcriptomic data generated using Affymetrix one-cycle (standard labelling protocol), two-cycle (small-sample protocol) and IVT-Express protocols with the Affymetrix ATH1 array using Arabidopsis root samples. Results obtained with each protocol are broadly similar. However, we show that there are 35 probe sets (of a total of 22810) that are misrepresented in the two-cycle data sets. Of these, 33 probe sets were classed as mis-amplified when comparisons of two independent publicly available data sets were undertaken.
Project description:Wheat seed germination directly affects wheat yield and quality. The wheat grains mainly include embryo and endosperm, and both play important roles in seed germination, seedling survival and subsequent vegetative growth. ABA can positively regulate dormancy induction and then negatively regulates seed germination at low concentrations. H2O2 treatment with low concentration can promote seed germination of cereal plants. Although various transcriptomics and proteomics approaches have been used to investigate the seed germination mechanisms and response to various abiotic stresses in different plant species, an integrative transcriptome analysis of wheat embryo and endosperm response to ABA and H2O2 stresses has not reported so far. We used the elite Chinese bread wheat cultivar Zhenmai 9023 as material and performed the first comparative transcriptome microarray analysis between embryo and endosperm response to ABA and H2O2 treatments during seed germination using the GeneChip® Wheat Genome Array Wheat seed germination includes a great amount of regulated genes which belong to many functional groups. ABA/H2O2 can repress/promote seed germination through coordinated regulating related genes expression. Our results provide new insights into the transcriptional regulation mechanisms of embryo and endosperm response to ABA and H2O2 treatments during seed germination
Project description:The phytohormone abscisic acid (ABA) promotes seed dormancy and inhibits seed germination and seedling development. It remains unclear how chromatin remodeling influences ABA responses. In the present study, an artificial microRNA targeting two Sucrose Non-Fermenting 2 (SNF2)-family chromatin remodeling ATPases, SPLAYED (SYD) and PHOTOPERIOD-INDEPENDENT EARLY FLOWERING1 (PIE1), was identified through unbiased forward genetic screenings of artificial microRNA (amiRNA)-expressing pooled seed libraries exhibiting ABA-insensitive seed germination. T-DNA insertional mutants of syd and pie1, along with amiRNA-expressing knockdown lines amiR-SYD and amiR-PIE1, confirmed that SYD, but not PIE1, is essential for promoting ABA-inhibition of seed germination. Transcriptome analyses revealed that the ABA catabolism gene CYP707A3 and the gibberellin (GA) biosynthesis genes GA20OX2, GA20OX3, GA3OX2, GA3OX3, and GA3OX4 were upregulated in amiR-SYD mutant seeds compared to control seeds under ABA treatment during germination. The ABA hyposensitivity observed in amiR-SYD mutants was reversed by treatment with uniconazole, an inhibitor of ABA catabolism and GA biosynthesis, suggesting that the reduced ABA sensitivity in amiR-SYD mutants results from increased ABA degradation and GA production. These findings demonstrate that the SYD-associated chromatin remodeling complex positively regulates ABA responses during seed germination, unlike its close homolog BRAHMA (BRM), which acts as a negative regulator of the ABA response.
Project description:Seed germination is a critical developmental stage in the life cycle of plants, and its regulation is essential for ensuring crop productivity, particularly under adverse environmental conditions. Here, we find that the Arabidopsis thaliana PRE-MRNA-PROCESSING (PRP21) is crucial for the regulation of abscisic acid (ABA) response of seed germination. Our RNA deep sequencing and poly(A) tag sequencing analyses reveal that PRP21 is involved in pre-mRNA splicing, genome-wide gene transcription, and mRNA 3' end processing, highlighting its multifunctional role in gene regulation. Furthermore, we find that PRP21 interacts with various splicing factors and small nuclear ribonucleoproteins, suggesting its involvement in spliceosome assembly. Additionally, we demonstrate that PRP21 negatively regulates the expression of ABA-responsive genes, such as ABSCISIC ACID-INSENSITIVE 3 (ABI3), ABSCISIC ACID-INSENSITIVE 5 (ABI5), EARLY METHIONINE-LABELED 1 (EM1), and EARLY METHIONINE-LABELED 6 (EM6), thereby modulating ABA response and seed germination. Our findings underscore the importance of PRP21 in coordinating transcriptional and post-transcriptional processes, and provide insights into the molecular mechanisms underlying seed germination, potentially guiding crop improvement for stress tolerance.
Project description:Seed germination is a critical developmental stage in the life cycle of plants, and its regulation is essential for ensuring crop productivity, particularly under adverse environmental conditions. Here, we find that the Arabidopsis thaliana PRE-MRNA-PROCESSING (PRP21) is crucial for the regulation of abscisic acid (ABA) response of seed germination. Our RNA deep sequencing and poly(A) tag sequencing analyses reveal that PRP21 is involved in pre-mRNA splicing, genome-wide gene transcription, and mRNA 3' end processing, highlighting its multifunctional role in gene regulation. Furthermore, we find that PRP21 interacts with various splicing factors and small nuclear ribonucleoproteins, suggesting its involvement in spliceosome assembly. Additionally, we demonstrate that PRP21 negatively regulates the expression of ABA-responsive genes, such as ABSCISIC ACID-INSENSITIVE 3 (ABI3), ABSCISIC ACID-INSENSITIVE 5 (ABI5), EARLY METHIONINE-LABELED 1 (EM1), and EARLY METHIONINE-LABELED 6 (EM6), thereby modulating ABA response and seed germination. Our findings underscore the importance of PRP21 in coordinating transcriptional and post-transcriptional processes, and provide insights into the molecular mechanisms underlying seed germination, potentially guiding crop improvement for stress tolerance.
Project description:Seed germination is a critical developmental stage in the life cycle of plants, and its regulation is essential for ensuring crop productivity, particularly under adverse environmental conditions. Here, we find that the Arabidopsis thaliana PRE-MRNA-PROCESSING (PRP21) is crucial for the regulation of abscisic acid (ABA) response of seed germination. Our RNA deep sequencing and poly(A) tag sequencing analyses reveal that PRP21 is involved in pre-mRNA splicing, genome-wide gene transcription, and mRNA 3' end processing, highlighting its multifunctional role in gene regulation. Furthermore, we find that PRP21 interacts with various splicing factors and small nuclear ribonucleoproteins, suggesting its involvement in spliceosome assembly. Additionally, we demonstrate that PRP21 negatively regulates the expression of ABA-responsive genes, such as ABSCISIC ACID-INSENSITIVE 3 (ABI3), ABSCISIC ACID-INSENSITIVE 5 (ABI5), EARLY METHIONINE-LABELED 1 (EM1), and EARLY METHIONINE-LABELED 6 (EM6), thereby modulating ABA response and seed germination. Our findings underscore the importance of PRP21 in coordinating transcriptional and post-transcriptional processes, and provide insights into the molecular mechanisms underlying seed germination, potentially guiding crop improvement for stress tolerance.