Rad50 ChIPseq in Drosophila wandering larval central nervous system and in embryos stage 16
Ontology highlight
ABSTRACT: Rad50 is overexpressed in larval brain compared to embryo and is likely linked to stage specific chromatin modification. To identify the targets of Rad50, ChIPseq with Rad50 antibody was done in duplicate on wandering larval brain and on embryo stage 16.
Project description:The initially homogeneous epithelium of the early Drosophila embryo differentiates into regional subpopulations with different behaviours and physical properties that are needed for morphogenesis. The factors at top of the genetic hierarchy that control these behaviours are known, but many of their targets are not. To understand how proteins work together to mediate differential cellular activities, we studied in an unbiased manner the proteomes and phosphoproteomes of the three main cell populations along the dorso-ventral axis during gastrulation using mutant embryos that represent the different populations. We detected 6111 protein groups and 6259 phosphosites of which 3399 and 3433 respectively, were differentially regulated. The changes in phosphosite abundance did not correlate with changes in host protein abundance, showing phosphorylation to be a regulatory step during gastrulation. Hierarchical clustering of protein groups and phosphosites identified clusters that contain known fate determinants such as Doc1, Sog, Snail and Twist. The recovery of the appropriate known marker proteins in each of the different mutants we used validated the approach, but also revealed that two mutations that both interfere with the dorsal fate pathway, Toll10B and serpin27aex do this in very different manners. Diffused network analyses within each cluster point to microtubule components as one of the main groups of regulated proteins. Functional studies on the role of microtubules provide the proof of principle that microtubules have different functions in different domains along the DV axis of the embryo. This repository is related to PXD046050 which represents the label-free proteome.
Project description:Neural precursors were isolated by laser capture microdissection from the sub-ventricular zone of cryosectioned brains of 4 wild type and 4 Nestin-Cre Mbd3flox/flox mice at E12.5, E14.5 and E16.5
Project description:The piRNA pathway controls transposon expression in animal germ cells, thereby ensuring genome stability over generations. piRNAs are maternally deposited and required for proper transposon silencing in adult offspring. However, a long-standing question in the field is the precise function of maternally deposited piRNAs and its associated factors during embryogenesis. Here, we probe the spatio-temporal expression patterns of several piRNA pathway components during early stages of development. Amongst those, factors required for transcriptional gene silencing (TGS) showed ubiquitous abundance in somatic and pole cells throughout the first half of embryogenesis. We further analysed the transcriptomes of various embryo stages and correlated these with the presence of selected chromatin marks. We found that a number of transposon families show bursts of transcription during early embryonic stages. Transposons heavily targeted by maternally deposited piRNAs accumulated repressive chromatin marks following their spike in expression. Furthermore, depletion of maternally deposited Piwi protein in early embryos resulted in increased expression of transposons targeted by inherited piRNAs and was accompanied by a strong loss of repressive chromatin marks at coding sequences. Overall, our data suggests a pivotal role for the piRNA pathway in transposon defence during Drosophila embryogenesis in somatic cells.
Project description:Areas and layers of the cerebral cortex are specified by genetic programs that are initiated in progenitor cells and then, implemented in postmitotic neurons. Here, we report that Tbr1, a transcription factor expressed in postmitotic projection neurons, exerts positive and negative control over both regional (areal) and laminar identity. Tbr1 null mice exhibited profound defects of frontal cortex and layer 6 differentiation, as indicated by down-regulation of gene-expression markers such as Bcl6 and Cdh9. Conversely, genes that implement caudal cortex and layer 5 identity, such as Bhlhb5 and Fezf2, were up-regulated in Tbr1 mutants. Tbr1 implements frontal identity in part by direct promoter binding and activation of Auts2, a frontal cortex gene implicated in autism. Tbr1 regulates laminar identity in part by downstream activation or maintenance of Sox5, an important transcription factor controlling neuronal migration and corticofugal axon projections. Similar to Sox5 mutants, Tbr1 mutants exhibit ectopic axon projections to the hypothalamus and cerebral peduncle. Together, our findings show that Tbr1 coordinately regulates regional and laminar identity of postmitotic cortical neurons. Mouse E14.5 neocortices and Postnatal day (P) 0.5 brains: E14.5 neocortices KO, 3; E14.5 neocortices WT, 3; Postnatal day (P) 0.5 brains frontal WT, 4; Postnatal day (P) 0.5 brains frontal KO, 4; Postnatal day (P) 0.5 brains parietal WT, 4; Postnatal day (P) 0.5 brains parietal KO, 4; Postnatal day (P) 0.5 brains occipital WT, 4; Postnatal day (P) 0.5 brains occipital KO, 4.
Project description:Apical progenitors from wild type and NestinCre:Mbd3Flox/Flox embryos at E12.5, E14.5 and E16.5 were used for gene expression microarray analyses to identify gene expression changes dependent upon a functional NuRD complex.
Project description:Basal-like breast cancer generally shows a good response to conventional cytotoxic but rapidly develops a resistant phenotype. To better understand the epigenetic changes underlying the acquisition of resistant properties, we treated the murine basal-like mammary carcinoma cell line G-2 for 48 hours with sublethal combination chemotherapy (Cyclophosphamide, Adriamycin, 5-Fluorouracil) and subsequently subjected them to RNA- and ChIP-sequencing.
Project description:Rad50 is a component of the conserved MRE11-RAD50-NBS1 (MRN) complex, which functions in genome stability and the cell’s ability to deal with stalled DNA replication forks. We identified Rad50 as a factor important for R-loop tolerance and thus mapped DNA:RNA hybrids in Rad50KO cells and compare them to previously reported wild-type and Sgs1KO profiles.
Project description:Members of the SWI/SNF chromatin-remodeling complex are among the most frequently mutated genes in human cancer. SWI/SNF complex controls self-renewal and differentiation in stem cell lineages but how this function relates to tumorigenesis is currently unclear. Here, we use Drosophila neuroblasts to demonstrate that the SWI/SNF component Osa (ARID1) prevents tumorigenesis in stem cell lineages by ensuring correct unidirectional lineage progression. Our transcriptome anaysis identifies Ham as a key Osa target gene. comparison of transcriptomes of wild type Drosophila melanogaster larval type II NB lineages (excluding neurons) and osa RNAi type II lineages containing mainly NB-like cells and INPs
Project description:The initially homogeneous epithelium of the early Drosophila embryo differentiates into regional subpopulations with different behaviours and physical properties that are needed for morphogenesis. The factors at top of the genetic hierarchy that control these behaviours are known, but many of their targets are not. To understand how proteins work together to mediate differential cellular activities, we studied in an unbiased manner the proteomes and phosphoproteomes of the three main cell populations along the dorso-ventral axis during gastrulation using mutant embryos that represent the different populations. We detected 6111 protein groups and 6259 phosphosites of which 3399 and 3433 respectively, were differentially regulated. The changes in phosphosite abundance did not correlate with changes in host protein abundance, showing phosphorylation to be a regulatory step during gastrulation. Hierarchical clustering of protein groups and phosphosites identified clusters that contain known fate determinants such as Doc1, Sog, Snail and Twist. The recovery of the appropriate known marker proteins in each of the different mutants we used validated the approach, but also revealed that two mutations that both interfere with the dorsal fate pathway, Toll10B and serpin27aex do this in very different manners. Diffused network analyses within each cluster point to microtubule components as one of the main groups of regulated proteins. Functional studies on the role of microtubules provide the proof of principle that microtubules have different functions in different domains along the DV axis of the embryo.