Project description:We test the effects of overexpressing RNAi proteins Dcr1, Rdp1, or Ago1 in wildtype, dcr1∆, ago1∆, or rdp1∆ cells. We find that overexpression does not generally affect H3K9me2 at euchromatic loci, but there are varying effects in H3K9me2 on centromeric heterochromatin. Examination of genome-wide enrichment in H3K9 dimethylation in fission yeast haploid cells
Project description:Heterochromatin protein 1 (HP1) proteins are important regulators of heterochromatin mediated gene silencing and chromosome structure and it is well known as the reader of the heterochromatin mark methylation of histone H3 lysine 9 (H3K9me). In Drosophila three different histone lysine methyl transferases (HKMTs) are associated with the methylation of H3K9; Su(var)3-9, Setdb1 and G9a. To gain insights on the dependence of HP1a on the three different HKMTs, the division of labor between these methyl transferases and the dependence of HP1a on H3K9me we have studied HP1a binding in relation to H3K9me in mutants of these HKMTs. We show that Su(var)3-9 is responsible for the HP1a H3K9me-dependent binding in pericentromeric regions while Setdb1 controls the HP1a H3K9me-dependent binding to cytological region 2L:31 and together with POF chromosome 4. HP1a binds to the promoters and within gene bodies of active genes in these three regions. More importantly, HP1a bound at promoters of active genes are independent of H3K9me and POF and is associated to heterochromatin protein 2 (HP2) and open chromatin. Our results supports a model where HP1a nucleates with high affinity independent of H3K9me in promoters of active genes and then spreads via H3K9 methylation and transient looping contacts with those H3K9me target sites. In total 44 samples; 2 replicates for each genotype and for each ChIP (HP1a, H3K9me2 and H3K9me3)
Project description:We use small RNA sequencing to look for spreading of secondary and tertiary siRNAs along transcripts targeted by ectopic hairpin-derived primary siRNAs. We find that signals within the 3' UTR inhibit siRNA spreading. sequencing of 20-30nt sRNAs from Argonaute immunoprecipitation
Project description:We mapped the genome-wide binding of the flagellar regulators FlhD, FlhC, and FliA in FLAG-tagged derivatives of E. coli K-12 MG1655 using ChIP coupled with deep sequencing (ChIP-seq). We identify new binding sites for each factor.
Project description:We mapped the genome-wide binding of C-terminally FLAG-tagged AraC in S. enterica subsp. enterica serovar Typhimurium strain 14028s using ChIP coupled with deep sequencing (ChIP-seq). We identified five putative target loci for AraC: upstream of araB/araC, araE, araJ, STM14_0178, and within sseD.
Project description:We mapped the genome-wide binding of sigma 70 in E. coli K-12 MG1655 and an hns mutant that is otherwise isogenic using ChIP coupled with deep sequencing (ChIP-seq). We show that intragenic binding of sigma 70 is increased in the hns mutant.
Project description:Chromatin immunoprecipitation of the Origin Recognition Complex (ORC) followed by hybridization to genome-wide tiling microarrays demonstrated that ORC does not localize to DAFC-34B after stage 10, despite a second round of replication initiation Comparison of ORC2 ChIP sample compared to input DNA for Drosophila egg chambers