In order to obtain a global picture regarding regulation of p53 in liver cells we used HepG2 hepatoma cells.We created two isogenic sub-cultures of HepG2 cells with altered expression of p53.
Chemotherapeutic agents induce the expression and activity of their clearing enzyme CYP3A4 by activating p53.
Specimen part, Cell line
View SamplesVitiligo is an acquired depigmentation of the skin inducing a marked alteration of the quality of life of affected individuals. Halting the disease progression and repigmenting the lesional skin represent the two faces of the therapeutic challenge in vitiligo. So far, none of them has been successfully addressed. Oxidative stress and immune system in genetically predisposed individuaLesionalparticipate to the complex pathophysiology of vitiligo. We performed a transcriptome and proteomic analysis on lesional, perilesional and non-depigmented skin of vitiligo patients compared to matched skin controLesionalof healthy subjects. Our results show that the WNT pathway, implicated in melanocytes differentiation, was found to be altered in vitiligo skin. We demonstrated that the oxidative stress decreases WNT expression/activation in keratinocytes and in melanocytes. We developed an ex vivo skin model that remains functional up to 15 days. We then confirmed the decreased activation of the WNT pathway in human skin subjected to oxidative stress. Finally, using pharmacological agents that activate the WNT pathway, we treated the ex vivo depigmented skins from vitiligo patients and successfully induced the differentiation of resident stem celLesionalinto pre-melanocytes supporting further exploration of WNT activators to repigment vitiligo lesions.
Transcriptional Analysis of Vitiligo Skin Reveals the Alteration of WNT Pathway: A Promising Target for Repigmenting Vitiligo Patients.
Specimen part
View SamplesObesity has been shown to increase risk for cardiovascular disease and type-2 diabetes. In addition, it has been implicated in aggravation of neurological conditions such as Alzheimer's. In the model organism Drosophila melanogaster, a physiological state mimicking diet-induced obesity can be induced by subjecting fruit flies to a solid medium disproportionately higher in sugar than protein (HSD) or that has been supplemented with a rich source of saturated fat (HFD). These flies can exhibit increased circulating glucose levels, increased triglyceride content, insulin-like peptide resistance, and behavior indicative of neurological decline, such as decreased climbing ability. We subjected Oregon-R-C flies to variants of the HSD, HFD, or normal (control) diet (ND), followed by a total RNA extraction from fly heads of each diet group for the purpose of Poly-A selected RNA-Sequencing. We targeted at least 50 million paired-end, stranded reads of 75 basepairs in size, and analyzed 4 biological replicates per dietary condition. Our objective was to identify the effects of obesogenic diets on transcriptome patterns, how they differed between obesogenic diets, and identify genes that may relate to pathogenesis accompanying an obesity-like state. Functional annotation and enrichment analysis among genes whose expression was significantly affected by the obesogenic diets indicated an overrepresentation of genes associated with immunity, metabolism, and hemocyanin in the HFD group, and CHK, cell cycle activity, and DNA binding and transcription in the HSD group. Heat map representation of genes affected by both diets illustrated a large fraction of differentially expressed genes between the two diet groups. Diets high in sugar and diets high in fat both have notableeffects on the Drosophila transcriptome in head tissue. The impacted genes, and how they may relate to pathogenesis in the Drosophila obesity-like state, warrant further experimental investigation. Our results also indicate differences in the effects of the HFD and HSD on expression profiles in head tissue of Oregon-R-C flies, despite the reportedly similar phenotypic impacts of the diets. Overall design: Flies were reared on one of three diets (high fat, high sugar, or normal). 6 replicates, with twenty flies each, from each diet treatment were collected for a total of 18 samples. The heads of the flies were then obtained, and RNA extracted from each of those samples. 4 of the RNA samples from each diet group (12 samples total) were sequenced.
RNA-Sequencing of <i>Drosophila melanogaster</i> Head Tissue on High-Sugar and High-Fat Diets.
Specimen part, Subject
View SamplesDendritic cells (DCs) and macrophages (MPs) are important for immunological homeostasis in the colon. We found that F4/80hi CX3CR1hi (CD11b+CD103-) cells account for 80% of mouse colonic lamina propria (cLP) MHC-IIhi cells. Both CD11c+ and CD11c- cells within this population were identified as MPs based on multiple criteria, including a MP transcriptome revealed by microarray analysis. These MPs constitutively released high levels of IL-10 at least partially in response to the microbiota via an MyD88-independent mechanism. In contrast, cells expressing low to intermediate levels of F4/80 and CX3CR1 were identified as DCs, based on phenotypic and functional analysis and comprise three separate CD11chi cell populations: CD103+CX3CR1-CD11b- DCs, CD103+CX3CR1-CD11b+ DCs and CD103-CX3CR1intCD11b+ DCs. In non-inflammatory conditions, Ly6Chi monocytes differentiated primarily into CD11c+, but not CD11c- MPs. In contrast, during colitis, Ly6Chi monocytes massively invaded the colon and differentiated into pro-inflammatory CD103-CX3CR1intCD11b+ DCs, which produced high levels of IL-12, IL-23, iNOS and TNF. These findings demonstrate the dual capacity of Ly6Chi blood monocytes to differentiate into either regulatory MPs or inflammatory DCs in the colon, and that the balance of these immunologically antagonistic cell types is dictated by microenvironmental conditions.
Inflammation switches the differentiation program of Ly6Chi monocytes from antiinflammatory macrophages to inflammatory dendritic cells in the colon.
No sample metadata fields
View SamplesWTX encodes a tumor suppressor, frequently inactivated in Wilms tumor, with both plasma membrane and nuclear localization. WTX has been implicated in beta-catenin turnover, but its effect on nuclear proteins is unknown. We report an interaction between WTX and p53, derived from the unexpected observation of WTX, p53 and E1B 55K colocalization within the characteristic cytoplasmic body of adenovirus-transformed kidney cells. In other cells without adenovirus expression, the C-terminal domain of WTX binds to the DNA binding domain of p53, enhances its binding to CBP, and increases CBP/p300-mediated acetylation of p53 at Lys 382. WTX knockdown accelerates CBP/p300 protein turnover and attenuates this modification of p53. In p53-reconstitution experiments, cell cycle arrest, apoptosis, and p53-target gene expression are suppressed by depletion of WTX. Together, these results suggest that WTX modulates p53 function, in part through regulation of its activator CBP/p300.
The WTX tumor suppressor enhances p53 acetylation by CBP/p300.
Cell line
View SamplesEffect of absence of interaction with MHC class II on memory CD4 T cells
Noncognate interaction with MHC class II molecules is essential for maintenance of T cell metabolism to establish optimal memory CD4 T cell function.
Sex, Specimen part
View SamplesThe small RNA payload of mammalian sperm undergoes dramatic remodeling during development, as several waves of microRNAs and tRNA fragments are shipped to sperm during post-testicular maturation in the epididymis. Here, we take advantage of this developmental process to probe the function of the sperm RNA payload in preimplantation development. We generated zygotes via intracytoplasmic sperm injection (ICSI) using sperm obtained from the proximal (caput) vs. distal (cauda) epididymis, then characterized development of the resulting embryos. Embryos generated using caput sperm significantly overexpress multiple regulatory factors throughout preimplantation development, and subsequently implant inefficiently and fail soon after implantation. Remarkably, microinjection of purified cauda-specific small RNAs into caput-derived embryos not only completely rescued preimplantation molecular defects, but also suppressed the postimplantation embryonic lethality phenotype. These findings reveal an essential role for small RNA remodeling during post-testicular maturation of mammalian sperm, and identify a specific preimplantation gene expression program responsive to sperm-delivered microRNAs. Overall design: Zygotes were generated by ICSI from sperm isolated from the testis, caput epididymis, or cauda epididiymis. Following fertilization by ICSI zygotes were developed to different stages of preimplantation development and were harvested for single-embryo RNA-Seq (Smart-Seq 2 protocol). For RNA injection experiments 3 hours after fertilization by ICSI RNA was injected using an Eppendorf Femtojet injection setup.
Small RNAs Gained during Epididymal Transit of Sperm Are Essential for Embryonic Development in Mice.
Cell line, Subject
View SamplesThe study was designed in order to identify genes differentially expressed when glucocorticoid signaling is blocked by a glucocorticoid-receptor antagonist (RU486 mifepristone) in the context of brain inflammation induced by bacterial lipopolysaccharide (LPS). LPS is only able to cause murine brain damage in our experimental conditions upon RU486 pre-treatment. Hence, the study may reveal potential candidate genes to mediate neuroprotection or neurotoxicity. Due to the factorial design of the experiment, RU486 main-effect could be dissociated from the effects resultant of RU486/inflammation interaction. In addition, brain dissection was conducted to verify the effects in the brain side ipsilateral or contralateral to the site of intracerebral LPS infusion.
Genes involved in the balance between neuronal survival and death during inflammation.
Sex, Age, Specimen part
View SamplesThe bromodomain and extraterminal (BET) protein Brd4 is a validated drug target in leukemia, yet its regulatory function in this disease is not well understood. Here, we show that Brd4 chromatin occupancy in acute myeloid leukemia closely correlates with the hematopoietic transcription factors (TFs) Pu.1, Fli1, Erg, C/EBPa, C/EBPß, and Myb at nucleosome-depleted enhancer and promoter regions. We provide evidence that these TFs, in conjunction with the lysine acetyltransferase activity of p300/CBP, facilitate Brd4 recruitment to their occupied sites to promote transcriptional activation. Moreover, chemical inhibition of BET bromodomains is found to suppress the functional output each hematopoietic TF, thereby interfering with essential lineage-specific transcriptional circuits in this disease. These findings reveal a chromatin-based signaling cascade comprised of hematopoietic TFs, p300/CBP, and Brd4, which supports leukemia maintenance and is suppressed by BET bromodomain inhibition. Overall design: PolyA selected RNA-Seq for drug treated or shRNA-expressing MLL-AF9 transformed acute myeloid leukemia cells (RN2)
BET Bromodomain Inhibition Suppresses the Function of Hematopoietic Transcription Factors in Acute Myeloid Leukemia.
No sample metadata fields
View SamplesAuxin is a key phytohormone regulating central processes in plants that include embryo development, lateral root growth and flower maturation among others. Auxin is sensed by a set of F-Box proteins of the TIR1/AFB3 family triggering auxin dependent responses by a pathway that involves an interplay between the Aux/IAA transcription repressors and the ARF transcription factors. We have previously shown that the AFB3 auxin receptor has a specific role in coordinating primary and lateral root growth to external and internal nitrate availability (Vidal et al., 2010). In this work, we used an integrated genomics, bioinformatics and molecular genetics approach to dissect regulatory networks acting downstream AFB3 that are activated by a transient nitrate treatment in Arabidopsis roots. Our systems approach unraveled key components of the AFB3 regulatory network leading to changes in lateral root growth in response to nitrate.
Systems approaches map regulatory networks downstream of the auxin receptor AFB3 in the nitrate response of Arabidopsis thaliana roots.
Specimen part, Treatment
View Samples