Project description:RAD21 is a subunit of cohesin. Cohesin is maninly known for its role in holding sister chromatids together during cell-division but it also plays a role in gene regulation. Genome wide study in MCF7 cells have shown that cohesin co-binds with estrogen receptor alpha at numerous sites. To identify estrogen sensitive genes that are influenced by cohesin, a microarray expression analysis was conducted in MCF7 cells lacking the cohesin subunit RAD21. Global changes in gene expression were identified in cells treated with Control/RAD21 siRNA and stimulated with estrogen/vehicle thereafter.
Project description:The Cohesin complex has recently been described to regulate gene expression. We wanted to determine the gene expression profile specific in mouse ES cells after depletion of the Cohesin subunit Rad21. We used microarrays to detail the global programme of gene expression underlying depletion of Rad21 and identified distinct early development related genes up-regulated and many pluripotency related genes downregulated. Rad21 was depleted in R1/E ES cells for 48h using esiRNAs against Rad21. An esiRNA against non-targeting Luciferase was used as a negative control
Project description:We used genome wide ChIP-seq to examine the chromatin histone changes after the knockdown of one of cohesin subunit, RAD21, in MCF7 breast cancer cells.
Project description:Estrogen signaling in breast cancer cells relies on long-range chromatin interactions connecting distal regulatory elements bound by the estrogen receptor 1 (ESR1) to target gene promoters. This ensures stimulus and subtype-specific transcriptional responses. Expanding on the function of CTCF and the cohesin complex in breast cancer, we demonstrate that the chromatin-looping factor ZNF143 binds the promoter of most early-response estrogen target genes connected to distal regulatory elements in ESR1-positive breast cancer cells. Its chromatin occupancy is unaffected by estrogen stimulation, supporting a stable three-dimensional genomic architecture within the early response to estrogen. Its loss abrogates the estrogen-induced transcriptional response and growth of breast cancer cells. When taking into account CTCF, ZNF143 and cohesin complex subunits, we show that chromatin-looping factors are genetically altered in over 20% of ESR1-positive primary breast tumors. Furthermore, the overexpression of ZNF143, CTCF and RAD21, a cohesin complex subunit, in ESR1-positive breast tumors associates with a worse clinical outcome. Overall, our results suggest that ZNF143 is a new critical effector of the estrogen response and highlights the contribution of the chromatin looping machinery to ESR1-positive breast cancer development. mRNA profiles of MCF-7 cells (siCtl or siZNF143) under vehicle (EtOH) or E2 (10 uM 17-beta oestradiol) stimulation
Project description:ChIP-Seq targeting the major cohesin core subunit RAD21 to represent cohesin occupancy and binding sites in cohesin-mutated (STA2 or RAD21 mutations) and wildtpye adult AMLs.
Project description:Analysis of estrogen receptor (ER)-positive MCF7 cell total RNA expression and polysome-assiciated RNA expression following treatment with estradiol (E2) and vehicle (etoh). We used expression microarrays to measure polysome association and total RNA abundance in E2 treated MCF7. These data, along with previously published data, show that genes that are upregulated by estrogen treatment are biased towards association with polysomes. MCF7 cells were grown in hormone depleted media for three days before a 1 hour treatment with E2 or 0.1 % ethanol (vehicle). Total RNA was collected using standard methods and polysome-association RNA from the same cells were collected using sucrose gradient fractionation. Both RNA populations were purified, labeled, and hybridized to Affymetrix Human Genest arrays.
Project description:Estrogen signaling in breast cancer cells relies on long-range chromatin interactions connecting distal regulatory elements bound by the estrogen receptor 1 (ESR1) to target gene promoters. This ensures stimulus and subtype-specific transcriptional responses. Expanding on the function of CTCF and the cohesin complex in breast cancer, we demonstrate that the chromatin-looping factor ZNF143 binds the promoter of most early-response estrogen target genes connected to distal regulatory elements in ESR1-positive breast cancer cells. Its chromatin occupancy is unaffected by estrogen stimulation, supporting a stable three-dimensional genomic architecture within the early response to estrogen. Its loss abrogates the estrogen-induced transcriptional response and growth of breast cancer cells. When taking into account CTCF, ZNF143 and cohesin complex subunits, we show that chromatin-looping factors are genetically altered in over 20% of ESR1-positive primary breast tumors. Furthermore, the overexpression of ZNF143, CTCF and RAD21, a cohesin complex subunit, in ESR1-positive breast tumors associates with a worse clinical outcome. Overall, our results suggest that ZNF143 is a new critical effector of the estrogen response and highlights the contribution of the chromatin looping machinery to ESR1-positive breast cancer development. Examination of genome-wide ZNF143 binding in MCF-7 cells
Project description:Analysis of estrogen receptor (ER)-positive MCF7 cell total RNA expression and polysome-assiciated RNA expression following treatment with estradiol (E2) and vehicle (etoh). We used expression microarrays to measure polysome association and total RNA abundance in E2 treated MCF7. These data, along with previously published data, show that genes that are upregulated by estrogen treatment are biased towards association with polysomes.
Project description:MTD project_description Inflammation and decreased stem cell function characterize organism aging, yet the relationship between these factors remains incompletely understood. This study shows that aged hematopoietic stem and progenitor cells exhibit increased ground-stage NF-κB activity, which enhances their responsiveness to undergo differentiation and loss of self-renewal in response to inflammation. The study identifies Rad21/cohesin as a critical mediator of NF-κB signals, by increasing chromatin accessibility of inter-/intra-genic and enhancer regions. Rad21/NF-κB are required for normal differentiation, but limit self-renewal of hematopoietic stem cells (HSCs) during aging and inflammation in an NF-κB dependent manner. HSCs from aged mice fail to downregulate Rad21/cohesin and inflammation/differentiation inducing signals in the resolution phase after acute inflammation. and The inhibition of cohesin/NF-κB is sufficient to revert the hypersensitivity of aged HSPCs to inflammation-induced differentiation. During aging, myeloid-biased HSCs with disrupted and naturally occurring reduced expression of Rad21/cohesin are increasingly selected over lymphoid-biased HSCs. Together, Rad21/cohesin mediated NF-κB signaling limits HSPC function during aging and selects for cohesin deficient HSCs with myeloid skewed differentiation.