Loss of muscle mass occurs in a variety of diseases including cancer, chronic heart failure, AIDS, diabetes and renal failure, often aggravating pathological progression. Preventing muscle wasting by promoting muscle growth has been proposed as a possible therapeutic approach. Myostatin is an important negative modulator of muscle growth during myogenesis and myostatin inhibitors are attractive drug targets. However, the role of the myostatin pathway in adulthood and the transcription factors involved in the signaling are unclear. Moreover recent results confirm that other TGF members control muscle mass. Using genetic tools we perturbed this pathway in adult myofibers, in vivo, to characterize the downstream targets and their ability to control muscle mass. Smad2 and Smad3 are the transcription factors downstream of myostatin/TGF and induce an atrophy program which is MuRF1 independent and requires FoxO activity. Furthermore Smad2/3 inhibition promotes muscle hypertrophy independent of satellite cells but partially dependent of mTOR signalling. Thus myostatin and Akt pathways cross-talk at different levels. These findings point to myostatin inhibitors as good drugs to promote muscle growth during rehabilitation especially when they are combined with IGF1-Akt activators.
Smad2 and 3 transcription factors control muscle mass in adulthood.
Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genomic binding of PAX8-PPARG fusion protein regulates cancer-related pathways and alters the immune landscape of thyroid cancer.
Specimen part, Treatment
View SamplesPAX8-PPARG fusion protein (PPFP) results from a t(2;3)(q13;p25) chromosomal translocation, is found in 30% of follicular thyroid carcinomas, and demonstrates oncogenic capacity in transgenic mice. A PPARG ligand, pioglitazone, is highly therapeutic in mice with PPFP thyroid carcinoma. We used our previously characterized transgenic mouse model of PPFP thyroid carcinoma to identify PPFP binding sites in vivo using ChIP-seq, and to identify genes and pathways regulated by PPFP with and without pioglitazone treatment via integration with RNA-seq and Affymetrix microarray data. This submission contains the Affymetrix microarray data. PPFP and pioglitazone regulated genes involved in lipid and fatty acid metabolism, ribosome function, immune processes, cell death and other cancer-related processes. The RNA-seq data yielded similar findings.
Genomic binding of PAX8-PPARG fusion protein regulates cancer-related pathways and alters the immune landscape of thyroid cancer.
Specimen part, Treatment
View SamplesOur data suggest that CNTF remodels the transcription profile of Mller (glial) cells leading to induction of networks associated with transcription, cell cycle regulation and inflammatory response. CNTF also appears to function as an inducer of gliosis in the retina. These studies provide new insights into the biological functions of cytokines in the retina.
Ciliary neurotrophic factor induces genes associated with inflammation and gliosis in the retina: a gene profiling study of flow-sorted, Müller cells.
Specimen part, Treatment, Time
View SamplesAs4.1 cells are a renin-expressing cell line commonly used to study the molecular regulation of the mouse renin gene. In the present study, the global gene expression profile was assessed in these cells under control conditions (VEHICLE) and after treatment with interleukin (IL) or hydrogen peroxide (HP), both of which negatively regulate mouse renin gene expression.
Regulation of renin gene expression by oxidative stress.
No sample metadata fields
View SamplesAtherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator.
ATF3 protects against atherosclerosis by suppressing 25-hydroxycholesterol-induced lipid body formation.
Sex, Specimen part
View SamplesUsing killer cell lectin-like receptor G1 as a marker to distinguish terminal effector cells from memory precursors, we found that despite their diverse cell fates both subsets possessed remarkably similar gene expression profiles and functioned as equally potent killer cells. However, only the memory precursors were capable of making IL-2 thus defining a novel effector cell that was cytotoxic, expressed granzyme B, and produced inflammatory cytokines in addition to IL-2. This effector population then differentiated into long-lived protective memory T cells capable of self-renewal and rapid re-call responses. Mechanistic studies showed that cells that continued to receive antigenic stimulation during the later stages of infection were more likely to become terminal effectors. Importantly, curtailing antigenic stimulation towards the tail-end of the acute infection enhanced the generation of memory cells. These studies support the decreasing potential model of memory differentiation and show that the duration of antigenic stimulation is a critical regulator of memory formation
Functional and genomic profiling of effector CD8 T cell subsets with distinct memory fates.
No sample metadata fields
View SamplesCD25, the high affinity interleukin-2 (IL-2) receptor alpha-chain, is rapidly upregulated by antigen-specific CD8+ T cells after T cell receptor stimulation. We demonstrated that during an acute viral infection, CD25 expression was dynamic, and a subset of virus-specific CD8+ T cells sustained CD25 expression longer than the rest. Examination of the in vivo fate of effector CD8+ T cells exhibiting differential responsiveness to IL-2 revealed that CD25lo cells, which were relatively less sensitive to IL-2, preferentially upregulated CD127 and CD62L and gave rise to the functional long-lived memory pool. In contrast, CD25hi cells that accumulate enhanced IL-2 signals, proliferated more rapidly, were prone to apoptosis, exhibited a more pronounced effector phenotype, and appeared to be terminally differentiated. Sustained IL-2 receptor signaling resulted in increased CD8+ T cell proliferation, higher granzyme B expression and exaggerated contraction after antigen clearance. These data support the hypothesis that prolonged IL-2 signals during priming promote terminal effector differentiation of CD8+ T cells.
Prolonged interleukin-2Ralpha expression on virus-specific CD8+ T cells favors terminal-effector differentiation in vivo.
Specimen part
View SamplesDmrt1 (doublesex and mab-3 related transcription factor 1) is a conserved transcriptional regulator of male differentiation required for testicular development in vertebrates. This study examines the result of conditional removal of Dmrt1 from Sertoli cells in P28 testis tissue.
DMRT1 prevents female reprogramming in the postnatal mammalian testis.
Sex, Specimen part
View Samples-catenin signaling is required for hair follicle development, but it is unknown whether it is sufficient to activate expression of hair follicle genes in embryonic skin. To address this we profiled gene expression in dermis from E15.5 KRT14-Cre Ctnnb1(Ex3)fl/+ embryos carrying an activating mutation in epithelial beta-catenin, and control littermate embryos.
Molecular heterogeneity in acute renal allograft rejection identified by DNA microarray profiling.
No sample metadata fields
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