Project description:At genome-wide level, loss of OsChz1 causes mis-regulation of thousands of genes and broad alterations of nucleosome occupancy as well as reduction of H2A.Z-enrichment within chromatin along the gene body and at TSS. While OsChz1 associates with chromatin regions enriched of repressive histone marks (H3K27me3 and H4K4me2), its loss does not affect the genome landscape of DNA methylation.
Project description:It is well understood how proteins regulate cell fate, both in normal development and disease. However, a substantial fraction of the genome is transcribed in a cell type- specific manner, producing long non-coding RNAs (lncRNA) rather than protein- coding transcripts. Here we systematically characterize transcriptional dynamics (both mRNA and lncRNA) during hematopoiesis and in hematological malignancies. We present de novo assembled transcriptome models and expression values for hematopoietic lncRNAs. We found lncRNAs to be regulated during differentiation and misregulated in disease. We assessed lncRNA function via an in vivo RNAi screen in a model of acute myeloid leukemia. With this approach, we identified several lncRNAs essential for leukemia maintenance, and found that a number act by promoting leukemia stem cell signatures. Leukemia blasts show a myeloid differentiation phenotype when these lncRNAs were depleted, and our data indicates that this effect is mediated via effects on the c-MYC oncogene.
Project description:Microarray comparisons of transcript level in wild-type Arabidopsis and eif3h mutant plants. Goal: To detect any change in transcript level between WT and eif3h mutant. BACKGROUND: The eukaryotic translation initiation factor eIF3 has multiple roles during the initiation of translation of cytoplasmic mRNAs. However, the contributions of individual subunits of eIF3 to the translation of specific mRNAs remain poorly understood. RESULTS: Working with stable reporter transgenes in Arabidopsis thaliana it was demonstrated that the h subunit of eIF3 contributes to the efficient translation initiation of mRNAs harboring upstream open reading frames (uORFs) in their 5’ leader sequence. uORFs, which can function as devices for translational regulation, are present in over 30% of Arabidopsis mRNAs, and are enriched among mRNAs for transcriptional regulators and protein modifying enzymes. Microarray comparisons of polysome loading in wild-type and eif3h mutant plants revealed that eIF3h generally helps to maintain efficient polysome loading of mRNAs harboring multiple uORFs. Independently, eIF3h also boosted polysome loading of mRNAs with long coding sequences. Moreover, the lesion in eIF3h revealed a concerted upregulation of translation for specific functional subgroups of mRNAs, including ribosomal proteins and proteins involved in photosynthesis. CONCLUSIONS: The intact eIF3h protein contributes to efficient translation initiation on 5’ leader sequences harboring multiple uORFs, although mRNA features independent of uORFs were also implicated. Moreover, our data suggest that regulons of translational control can be revealed by mutations in generic translation initiation factors. Keywords: mutant, total RNA
Project description:We found two DNA binding proteins, CRP and PepA, associate at the membrane. This study was performed to determine if their interaction affects transcription activity..
