Project description:Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to analyze the effect of telomerase inhibition on TNFM-NM-1-induced genome-wide p65 binding in HeLa cells. By obtaining over 40 million uniquely mappable reads per sample from ChIP-seq, maps for TNFM-NM-1-induced p65 binding in absence and presence of an hTERT inhibitor, MST-312, were generated. As expected, TNFM-NM-1 treatment significantly increased genome-wide p65 occupancy. Interestingly, when cells were treated with MST-312 prior to TNFM-NM-1 stimulation, the number of p65 binding sites was reduced. In addition, some binding sites, including important p65 targets like IL6 and TNF, showed a reduced p65 occupancy with a minimum fold change of 1.5, after MST-312 exposure. Taken together, our ChIP-seq data indicate that telomerase is required for optimal p65 binding at a small proportion of p65 target sites upon inflammatory stimuli. Examination of p65 binding in HeLa cells in absence and presence of TNFM-NM-1 and MST-312.
Project description:HeLa cells were stably transfected using the Tet-On® Advanced Cell Line system with Wildtype, G392E and Delta Neuroserpin with neuroserpin expression induced with doxycycline. Gene expression was examined in the absence or presence of 2 ug/ml doxycycline.
Project description:Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to analyze the effect of telomerase inhibition on TNFα-induced genome-wide p65 binding in HeLa cells. By obtaining over 40 million uniquely mappable reads per sample from ChIP-seq, maps for TNFα-induced p65 binding in absence and presence of an hTERT inhibitor, MST-312, were generated. As expected, TNFα treatment significantly increased genome-wide p65 occupancy. Interestingly, when cells were treated with MST-312 prior to TNFα stimulation, the number of p65 binding sites was reduced. In addition, some binding sites, including important p65 targets like IL6 and TNF, showed a reduced p65 occupancy with a minimum fold change of 1.5, after MST-312 exposure. Taken together, our ChIP-seq data indicate that telomerase is required for optimal p65 binding at a small proportion of p65 target sites upon inflammatory stimuli.
Project description:The HeLa cell line is the first human-derived immortalized cell line, one of the most widely used cell lines in the world. While many researches had pointed out the heterogeneity of HeLa cells across laboratories and the low repeatability of experiments performed on HeLa cells, the reason how these heterogeneities generated is little known. We sorted cells into single cells, cultured them to single clones and performed multi-omics sequencing. The single cell-derived clones exhibited persistent growth variation both in vitro and in vivo. The corresponding WGS analysis revealed the single clones diverse in copy number even at the whole chromosome level. Our work explored the intrinsic mechanisms of the low repeatability of cell line experiments. We also provided a resource for single cell-derived clones.
Project description:HeLa cell line is frequently used in biomedical research, however little is known about N-glycan structures expressed on individual glycoproteins of this complex sample. We characterized site-specific N-glycosylation of HeLa N-glycoproteins using a complex workflow based on high and low energy tandem mass spectrometry experiments and rigorous data evaluation. The analyses revealed high amount of bovine serum contaminants compromising previous results focusing on released glycan analysis. We reliably identified 43 (human) glycoproteins, 69 N-glycosylation sites and 178 glycopeptides following an acetone precipitation based sample enrichment step. HeLa glycoproteins were found to be highly fucosylated and in several cases localization of the fucose (core or antenna) could also be determined based on low energy tandem mass spectra. High-mannose sugars were expressed in high amounts as expected in case of a cancer cell line. Our method enabled the detailed characterization of site-specific N-glycosylation of several glycoproteins expressed in HeLa. Furthermore, we were the first to experimentally prove the existence of 31 glycosylation sites, where previously presence of glycosylation was only predicted based on the existence of the consensus sequon.