Project description:The series was designed to obtain gene expression patterns of TNF-alpha stimulated THP-1 cells. Keywords: TNF-alpha stimulation This series represents a group of 15 samples in two groups: 7 samples derived from not stimulated THP-1 cells, 8 from THP-1 cells stimulated with TNF-alpha in a final concentration of 5 ng/ml for 60 min.
Project description:Effect of TNF-alpha on microRNAs levels in Human Umbilical Endothelial Cells (HUVECs). HUVEC that were treated or not for 2 or 24 hours with TNF (10 ng/ml). Duplicate samples (1 or 2) of two different isolations of HUVEC (A or B)
Project description:Unraveling the complexity of transcriptional programs coded by different cell types has been one of the central goals of cell biology. Using genome-wide location analysis, we examined how two different cell types generate different responses to the NF-kappaB signaling pathway. We showed that, after tumor necrosis factor-alpha (TNF-alpha) treatment, NF-kappaB p65 subunit binds to distinct genome locations and subsequently induces different subsets of genes in human monocytic THP-1 cells versus HeLa cells . Interestingly, the differential p65 binding in two cell types correlates with pre-existing cell-type specific enhancers prior to TNF-alpha stimulation, marked by histone modifications. We also found that two transcription factors, PU.1 and C/EBPalpha, appear to synergistically mediate enhancer creation and affect NF-kappaB target selection in THP-1 cells. In HeLa cells, co-expression of PU.1 and C/EBPalpha conferred TNF-alpha responsiveness to a subset of THP-1 specific NF-kappaB target genes. These results suggest that the diversity of transcriptional programs in mammalian cells arises, at least in part, from pre-existing enhancers that are established by cell specific transcription factors. We used Affymetrix microarray (GPL570) to obtain gene expression data for THP1 and HeLa cells before and after TNF-alpha treatment.
