Project description:The goals of this study are to study the regulatory network of the two maize endosperm-specific transcription factors O2 and PBF by 16-DAP endosperm transcriptome profiling (RNA-seq) of their mutants and wild type. The results utilize the expression pattern of global genes regulated by PBF and O2 to elucidate their control for storage compounds synthesis in maize kernels.
Project description:The goals of this study are to study the regulatory network of the two maize endosperm-specific transcription factors O2 and PBF by 16-DAP endosperm transcriptome profiling (RNA-seq) of their mutants and wild type. The results utilize the expression pattern of global genes regulated by PBF and O2 to elucidate their control for storage compounds synthesis in maize kernels. The 16-DAP endosperm transcriptome of wild type (WT) and mutants including opaque2, PbfRNAi and PbfRNAi;o2 were generated by RNA-seq with three biological replicates per genotype on Illumina HiSeqTM2500.
Project description:1 g samples of maize seedling leaf bases were collected from the wild-type (Zheng58) plants and the mutants (bzu3-2). we undertook glycoproteomics analyses of the N-glycans. Based on the libraries of maize protein group and plant N-glycosylation modification in the Uniprot database, we identified 2,194 intact N-glycopeptides, and quantified 181 differentially expressed intact N-glycopeptides (DEGPs)
Project description:The contribution of epigenetic alterations to natural variation for gene transcription levels remains unclear. In this study, we investigated the functional targets of the maize chromomethylase ZMET2 in multiple inbred lines to determine whether epigenetic changes conditioned by this chromomethylase are conserved or variable within the species. Gene expression microarrays were hybridized with RNA samples from the inbred lines B73 and Mo17, and from near-isogenic derivatives containing the loss-of-function allele zmet2-m1. A set of 126 genes that displayed statistically significant differential expression in zmet2 mutants relative to wild-type plants in at least one of the two genetic backgrounds were identified. Analysis of the transcript levels in both wild-type and mutant individuals revealed that only 10% of these genes were affected in zmet2 mutants in both B73 and Mo17 genetic backgrounds. Over 80% of the genes with expression patterns affected by zmet2 mutations display variation for gene expression between wild-type B73 and Mo17 plants. Further analysis was performed for seven genes that were transcriptionally silent in wild-type B73, but expressed in B73 zmet2-m1, wild-type Mo17 and Mo17 zmet2-m1 lines. Mapping experiments confirmed that the expression differences in wild-type B73 relative to Mo17 inbreds for these genes were caused by cis-acting regulatory variation. Methylation-sensitive PCR and bisulphite sequencing demonstrated that for five of these genes the CpNpG methylation in the wild-type B73 genetic background was substantially decreased in the B73 zmet2-m1 mutant and in wild-type Mo17. A survey of eight maize inbreds reveals that each of these five genes exhibit transcriptionally silent and methylated states in some inbred lines and unmethylated, expressed states in other inbreds, providing evidence for natural variation in epigenetic states for some maize genes. Keywords: mutant versus wild-type comparison in two inbred genotypes
Project description:The basidiomycete Ustilago maydis causes smut disease in maize. Colonization of the host plant is initiated by direct penetration of cuticle and cell wall of maize epidermis cells. The invading hyphae are surrounded by the plant plasma membrane and proliferate within the plant tissue. We identified a novel secreted protein, termed Pep1. Disruption mutants of pep1 are not affected in saprophytic growth and develop normal infection structures. However, Δpep1 mutants fail to penetrate the epidermal cell wall and elicit a strong plant defense response. Using Affymetrix maize arrays we identified about 110 plant genes which are differentially regulated in Δpep1 and wild type infections during the penetration stage.
Project description:Maize RNA Polymerase D1 (RPD1), the largest subunit of RNA polymerase IV (Pol IV), is required for normal plant development, repression of transposable elements (TEs), and for the regulation of specific alleles associated with TEs. Here, we define the nascent transcriptomes of rpd1 mutant and wild-type (WT) seedlings using global run-on sequencing (GRO-seq) to identify the broader targets of RPD1-based transcriptional regulation. Surprisingly, although TE-like sequences comprise >85% of the maize genome, most TEs are not transcribed at the seedling stage, even in rpd1 mutants. Profile comparisons identify the global set of genes and TEs whose transcription is altered in the absence of RPD1, in some cases in antisense orientation. These results indicate that maize Pol IV specifies Pol II-based transcriptional regulation for certain regions of the maize genome.
Project description:Maize RNA Polymerase D1 (RPD1), the largest subunit of RNA polymerase IV (Pol IV), is required for normal plant development, repression of transposable elements (TEs), and for the regulation of specific alleles associated with TEs. Here, we define the nascent transcriptomes of rpd1 mutant and wild-type (WT) seedlings using global run-on sequencing (GRO-seq) to identify the broader targets of RPD1-based transcriptional regulation. Surprisingly, although TE-like sequences comprise >85% of the maize genome, most TEs are not transcribed at the seedling stage, even in rpd1 mutants. Profile comparisons identify the global set of genes and TEs whose transcription is altered in the absence of RPD1, in some cases in antisense orientation. These results indicate that maize Pol IV specifies Pol II-based transcriptional regulation for certain regions of the maize genome. Nuclei isolated from 10 wild-type and 10 rpd1 mutant seedlings were pooled and used to make two global run-on sequencing libraries.