Project description:Cis-regulatory elements control gene expression in time and space and their disruption can lead to pathologies. Reporter assays allow the functional validation of enhancers and other regulatory elements, and transgenic mice provide a powerful tool to study gene regulation in vivo. However, these experiments are time-consuming and inefficient. Here, we increase the throughput of transgenic reporter assays by using a piggyBac transposon-based system, and use it to decode the regulatory landscape of atrial fibrillation, a prevalent cardiac arrhythmia. We systematically interrogated ten human atrial fibrillation associated loci, finding five new cardiac-specific enhancers. We also connected novel genes to atrial fibrillation through genome editing and three-dimensional chromatin structure analysis. Of note, we identified a bivalent regulatory element in the second intron of the CAV1 gene at the 7q31 locus, differentially acting upon four genes. Our approach also detected negative regulatory elements such as an ubiquitous silencer in the 16q22 locus that regulates ZFHX3 and can outcompete heart enhancers. Our study characterizes the function of new genetic elements that might be of relevance for the better understanding of gene regulation in cardiac arrhythmias. Thus, we have established a new framework for the efficient dissection of the genetic contribution to common human diseases.
Project description:The goal of this study is to improve the quality, efficiency, and sustainability of milk production by improving the understanding of the function of cis-regulatory elements in regulating the bovine mammary gland. To this end, we have characterized the non-lactating and lactating mammary gland transcriptomes by whole transcriptome shotgun sequencing (RNA-seq). We will identify cis-regulatory elements in the non-lactating and lactating bovine mammary gland genome-wide. Finally, we will annotate and characterize mammary gland cis-regulatory elements by computational analysis and identify high-resolution genome-wide in vivo footprints of diverse trans-acting-factors (TF), over-represented TF bindings sites and overlapping SNPs.
Project description:We investigated the transcriptional activation and cis-regulatory elements of effector ISGs in CD8+ murine dendritic cells (DCs) stimulated with IFN-beta. We analysed gene repression changes and characterized activated cis-regulatory regions. Binding of ISGF3 subunits (IRF9, Stat1, and Stat2) and other transcription factors, DNA motifs, and chromatin status were also determined.
Project description:Although most disease-causing variants are within coding region of genes, it is now well established that cis-acting regulatory sequences, depending on 3D-chromatin organization, are required for temporal and spatial control of gene expression. Disruptions of such regulatory elements and/or chromatin conformation are likely to play a critical role in human genetic disease. Hence, recurrent monoallelic cases of the most common hereditary type of nonsyndromic hearing loss (i.e. DFNB1) carrying out only one identified pathogenic allele, led to strongly suggest the presence of uncharacterized distal cis-acting elements in the missing allele. Herewith, we study the spatial organization of a large DFNB1 locus encompassing the gap junction protein beta 2 (GJB2) gene, the most frequently mutated gene in this inherited hearing loss, with the chromosome conformation capture carbon copy technology (5C). By combining this approach with functional activity reporter assays and mapping of CCCTC-binding factor (CTCF) along the DFNB1 locus by quantitative real-time PCR chromatin immunoprecipitation, we identify a novel set of cooperating GJB2 cis-acting elements and propose a DFNB1 three-dimensional looping regulation model. A loop chromatin forming, allows bringing closer enhancers to the GJB2 promoter, but also avoids GJB2 silencing with an enhancer-blocking insulator activity.