Project description:The barley brittle stem mutants, fs2, designated X054 and M245, have reduced levels of cellulose compared with their isogenic parents Ohichi and Shiroseto. A custom-designed microarray, based on Agilent technology and including genes involved in cell wall metabolism, was used to compare transcript levels in the mutant and parental lines. For both mutants, the microarray revealed a marked decrease in mRNA for the HvCesA4 cellulose synthase gene in specific zones of stem internodes, and this was confirmed by quantitative PCR.
Project description:The barley brittle stem mutants, fs2, designated X054 and M245, have reduced levels of cellulose compared with their isogenic parents Ohichi and Shiroseto. A custom-designed microarray, based on Agilent technology and including genes involved in cell wall metabolism, was used to compare transcript levels in the mutant and parental lines. For both mutants, the microarray revealed a marked decrease in mRNA for the HvCesA4 cellulose synthase gene in specific zones of stem internodes, and this was confirmed by quantitative PCR. Genes expression was measured for the upper and lower zones from the 4th internodes of stems. Plant were at Zadocks developmental stage 49. Gene expression was compared between mutants and their wildtype parents.
Project description:We use targeted bisulfite PCR and next-generation 454 sequencing of multiple amplicons to analyze the association of cis-regulated allele-specific methylation (ASM) with multiple complex disease-associated variants in a population of 82 individuals. We detect ASM at four variants implicated in complex phenotypes such as ulcerative colitis and AIDS progression disease (rs10491434), Celiac disease (rs2762051), Crohn’s disease, IgA nephropathy and early-onset inflammatory bowel disease (rs713875) and height (rs6569648). 82 samples analysed
Project description:Histone modifications are important markers of function and chromatin state, yet the DNA elements that direct them to specific locations in the genome are poorly understood. Here we use the genetic variation in Yoruba lymphoblastoid cell lines as a natural experiment to identify genetic differences that affect histone marks and to better understand their relationship with transcriptional regulation. Across the genome, we identified hundreds of quantitative trait loci that impact histone modification or RNA polymerase (PolII) occupancy. In many cases the same variant is associated with quantitative changes in multiple histone marks and PolII, as well as in DNaseI sensitivity and nucleosome positioning, indicating that these molecular phenotypes often share a single underlying genetic cause. Variants that impact chromatin at distal regulatory sites frequently also direct changes in chromatin and gene expression at associated promoters; while most of these distal regulators enhance promoter activity, some act as distal chromatin silencers. Finally, we find that polymorphisms in transcription factor binding sites are often causally responsible for variation in local histone modification. In summary, the class of variants identified here generate coordinated changes in chromatin both locally and sometimes at distant locations, frequently drive changes in gene expression, and likely play an important role in the genetics of complex traits. ChIP-seq of RNA Polymerase II and 4 histone modifications (H3K4me1, H3K4me3, H3K27ac, H3K27me3) in 10 unrelated Yoruba HapMap lymphoblastoid cell lines