The mammalian brain is complex, with multiple cell types performing a variety of diverse functions, but exactly how each cell type is affected in aging remains largely unknown. Here we performed a single-cell transcriptomic analysis of young and old mouse brains. We provide comprehensive datasets of aging-related genes, pathways and ligand–receptor interactions in nearly all brain cell types. Our analysis identified gene signatures that vary in a coordinated manner across cell types and gene sets that are regulated in a cell-type specific manner, even at times in opposite directions. These data reveal that aging, rather than inducing a universal program, drives a distinct transcriptional course in each cell population, and they highlight key molecular processes, including ribosome biogenesis, underlying brain aging. Overall, these large-scale datasets provide a resource for the neuroscience community that will facilitate additional discoveries directed towards understanding and modifying the aging process. Overall design: Total of 16 mice brains with raw data for 50,212 single cells and processed data for 37,089 single cells
Single-cell transcriptomic profiling of the aging mouse brain.
Specimen part, Subject
View SamplesMutation of marA, rob, and soxS causes a clinical strain of E.coli to be attenuated at d3 post-infection in a mouse model of pyelonephritis, here we extract RNA at d2 post infection to analyze transcriptional differences between the two strains.
SoxS increases the expression of the zinc uptake system ZnuACB in an Escherichia coli murine pyelonephritis model.
Specimen part
View SamplesPurpose: We observed protein homeostasis modulations when anc-1 is knocked-down. We wanted to measure changes in gene expression profiles following this manipulation. Methods: We treated wild type (strain N2) or polyQ35-YFP (strain AM140) nematodes, which express toxic aggregative proteins that challenge their protein homeostasis, with anc-1 RNAi until day six of adulthood, and compared their gene expression levels to those of untreated worms. Results: The knockdown of anc-1 leads to modified expression levels of hundreds of genes. There is an enrichment of transcription factors and protein homeostasis modulators, such as E3 ubiquitin ligases. Conclusions: anc-1 regulates protection from toxic aggregative proteins, at least partially, by regulating the expression of genes that encode protein homeostasis factors. Overall design: Wild type strain, three repeats; polyQ35-YFP strain, four repeats. Each repeat has two conditions: untreated (EV), and RNAi toward anc-1.
Gene expression modulation by the linker of nucleoskeleton and cytoskeleton complex contributes to proteostasis.
Cell line, Subject
View SamplesThe objective of this study is to identify the genes that are up-regulated amid proteasome dysfunction to facilitate the discovery of proteolytic pathways that are activated as a compensatory response to proteasome inhibition. Proteasome is a large multi-component proteolytic complex in the cell. It is responsible for the constitutive turn-over of many cellular proteins as well as the degradation of oxidized and/or unfolded proteins. With such a fundamental role in the cell, disruption of proteasome understandably can lead to disastrous outcome. Oxidative stress has been postulated as the driving mechanism for aging. Oxidatively modified proteins, which usually have lost their activity, require immediate removal by proteasome to maintain normal cellular function. Dysfunction of proteasome has also been linked to neuro-degenerative diseases such as Alzheimers and Parkinsons diseases, those that are most commonly seen in aged population. There is more than one proteolytic pathway in the cell, and it has been reported that obstruction of any one of these pathways may enhance the activity of the others. Proteasomal function has been found to have decreased during aging, prompting researchers to hypothesize that failure to remove oxidized proteins may play an important role in aging. It would be interesting to determine the other proteolytic pathways that are activated after proteasome inhibition by a relatively specific inhibitor epoxomicin to help understand their roles in aging processes.
Iron regulatory protein 2 turnover through a nonproteasomal pathway.
No sample metadata fields
View SamplesRescuing the function of mutant p53 protein is an attractive cancer therapeutic strategy. Using the NCI anticancer drug screen data, we identified two compounds from the thiosemicarbazone family that manifest increased growth inhibitory activity in mutant p53 cells, particularly for the p53R175 mutant. Mechanistic studies reveal that NSC319726 restores WT structure and function to the p53R175 mutant. This compound kills p53R172H knock-in mice with extensive apoptosis and inhibits xenograft tumor growth in a 175-allele specific mutant p53 dependent manner. This activity depends upon the zinc ion chelating properties of the compound as well as redox changes. These data identify NSC319726 as a p53R175 mutant reactivator and as a lead compound for p53 targeted drug development.
Allele-specific p53 mutant reactivation.
Specimen part, Cell line, Treatment
View SamplesAnalysis of gene expression profiles in MEF cell lines in the absence or presence of STAT3 following IFNa stimulation. This study is to unveil possible role of STAT3 during type I IFN-mediated gene induction and functions.
STAT3 negatively regulates type I IFN-mediated antiviral response.
Cell line
View SamplesImmunosuppression is needed in HLA identical sibling renal transplantation. We conducted a tolerance trial in this patient cohort using Alemtuzumab induction, donor hematopoietic stem cells, tacrolimus/mycophenolate immunosuppression converted to sirolimus, planning complete drug withdrawal by 24 months post-transplantation. After an additional 12 months with no immunosuppression, normal biopsies and renal function, recipients were considered tolerant. Twenty recipients were enrolled. Of the first 10 (>36 months post-transplantation), 5 had immunosuppression successfully withdrawn for 16-36 months (tolerant), 2 had disease recurrence and 3 had subclinical rejection in protocol biopsies (non-tolerant). Microchimerism disappeared after 1 year, and CD4+CD25highCD127-FOXP3+ T cells and CD19+IgD/M+CD27- B cells increased to 5 years post-transplantation in both groups, whereas immune/inflammatory gene expression pathways in the peripheral blood and urine were differentially downregulated in tolerant compared to non-tolerant recipients. Therefore, in this HLA identical renal transplant tolerance trial, absent chimerism, Treg and Breg immunophenotypes were indistinguishable between tolerant and non-tolerant recipients, but global genomic changes indicating immunomodulation were observed only in tolerant recipients.
Genomic biomarkers correlate with HLA-identical renal transplant tolerance.
Specimen part, Time
View SamplesTo identify early processes in carcinogenesis, we used an in vitro model, based on the initiating event in cervical cancer, human papillomavirus (HPV) transformation of keratinocytes. We compared gene expression in primary keratinocytes (K) and HPV16-transformed keratinocytes from early (E) and late (L) passages, and from benzo[a]pyrene treated L cells (BP). The transformed cells exhibit similar transcriptional changes to clinical cervical carcinoma. We revealed a contraction in expression of the apoptotic network during HF1 cell transformation, which affected the ability of L and BP cells to execute apoptosis, but did not lead to resistance to apoptotic stimuli. The contraction in the apoptotic machinery during the process of transformation was accompanied by a switch from apoptosis to necrosis in response to CDDP. The shrinkage of the pro- and anti-apoptotic networks appears to be part of a general contraction in the number of genes transcribed in L and BP cells. We also identified a large group of genes with induced expression, which are involved in cell metabolism and cell cycle, suggesting increased investment of the transformed cell in cellular proliferation. We hypothesize that the decrease in expression of many diverse pathways, including the pro- and anti-apoptotic networks, cuts the energy requirements for cell maintenance, allowing energy to be diverted towards rapid cell proliferation. This study supports the hypothesis that the process of cancer transformation may be accompanied by a shift from apoptosis to necrosis.
Shift from apoptotic to necrotic cell death during human papillomavirus-induced transformation of keratinocytes.
Specimen part, Cell line
View SamplesFoxp3+ regulatory T cells (Treg cells) maintain immunological tolerance and their deficiency results in fatal multi-organ autoimmunity. Although heightened T cell receptor (TCR) signaling is critical for the differentiation of Treg cells, the role of TCR signaling in Treg cell function remains largely unknown. Here we demonstrate inducible ablation of the TCR results in Treg cell dysfunction which cannot be attributed to impaired Foxp3 expression, decreased expression of Treg cell signature genes or altered ability to sense and consume interleukin 2. Rather, TCR signaling was required for maintaining the expression of a limited subset of genes comprising 25% of the activated Treg cell transcriptional signature. Our results reveal a critical role for the TCR in Treg cell suppressor capacity.
Continuous requirement for the TCR in regulatory T cell function.
Specimen part
View SamplesAs Prdm16 deficiency reduces self-renewal potential and depletes neural stem cells in culture we decided to investigate the underlying molecular mechanisms of the neural stem cells depletion in the Prdm16 deficient animals. For the experiment we used Prdm16Gt(OST67423)Lex (Prdm16LacZ) genetrap mice obtained from the NIH Mutant Mouse Regional Resource Center (http://www.mmrrc.org/).
Prdm16 promotes stem cell maintenance in multiple tissues, partly by regulating oxidative stress.
Specimen part
View Samples