Project description:We utilized MNase-seq to profile nucleosome positions in wild type (Ax2) and ChdC null cells both in growing cells and a partially developed state (loose-mound) to study changes in nucleosome positioning and occupancy during development and the impact the deletion of ChdC an ATP-dependent chromatin remodeller has on nucleosome positioning and occupancy. As a control for MNase sequence bias we also digested naked DNA with MNase.
Project description:Genome-wide maps of nucleosome positioning in mouse ES cells with control shRNA and on Smarcad1 KD. MNase-seq data for human colo829 cells are also included.
Project description:We have employed MNase-Seq technology to determine the nucleosome positioning across the Ly49-expressing RMA cell line. This information was compared to the default nucleosome landscape of these cells as predicted by NuPop computations to identify transcription factor binding site regions that significantly deviate from our predictions, potentially indicating an interfering role for nucleosome binding at these sites. We report that expressed Ly49 genes significantly deviate in their nucleosome coverage at AML-1a sites when compared to other, non-expressed Ly49 genes within the same sample. This information has implications for our understanding of NK cell biology, and also presents the Ly49 family as a convenient model system for discovering how various genetic and epigenetic elements impact expression state, since Ly49 genes are stochastically expressed within a given population, but have similar transcription factor requirements. It is our hope that other work on the epigenetic control of gene expression can benefit from this model system.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:MNase-Seq and ChIP-Seq have evolved as popular techniques to study chromatin and histone modification. Although many tools have been developed to identify enriched regions, software tools for nucleosome positioning are still limited. We introduce a flexible and powerful open-source R package, PING 2.0, for nucleosome positioning using MNase-Seq data or MNase- or sonicated- ChIP-Seq data combined with either single-end or paired-end sequencing. PING uses a model-based approach, which enables nucleosome predictions even in the presence of low read counts. We illustrate PING using two paired-end datasets from Saccharomyces cerevisiae and compare its performance to nucleR and ChIPseqR.