Albeit increased serum CK level and abnormal muscle histology are always present, boys with DMD are phenotipically indistinguishable from the normal ones at birth and, in their first years of life, acquire early motor milestones at normal times. A clear defect in muscle function becomes generally apparent by the end of the second year. As the disease is typically diagnosed between the ages of 3 and 7, the first two years are often considered and referred to as clinically presymptomatic.
Gene expression profiling in the early phases of DMD: a constant molecular signature characterizes DMD muscle from early postnatal life throughout disease progression.
Sex, Age
View SamplesHere, we show that functional loss of a single gene is sufficient to confer constitutive milk protein production and protection against mammary tumor formation. Caveolin-3 (Cav-3), a muscle-specific caveolin-related gene, is highly expressed in striated and smooth muscle cells. We demonstrate that Cav-3 is also expressed in myoepithelial cells within the mammary gland. To determine if genetic ablation of Cav-3 expression affects adult mammary gland development, we next studied the phenotype(s) of Cav-3 (-/-) null mice. Interestingly, detailed analysis of Cav-3 (-/-) virgin mammary glands shows dramatic increases in ductal thickness, side-branching, and the development of extensive lobulo-alveolar hyperplasia, akin to the changes normally observed during pregnancy and lactation. Analysis by genome-wide expression profiling reveals the upregulation of gene transcripts associated with pregnancy/lactation, mammary stem cells, and human breast cancers, consistent with a constitutive lactogenic phenotype. The expression levels of three key transcriptional regulators of lactation, namely Elf5, Stat5a, and c-Myc are also significantly elevated. Experiments with pregnant mice directly show that Cav-3 (-/-) mice undergo precocious lactation. Finally, using orthotopic implantation of a transformed mammary cell line (known as Met-1), we demonstrate that virgin Cav-3 (-/-) mice are dramatically protected against mammary tumor formation. Interestingly, Cav-3 (+/-) mice also show similar protection, indicating that even reductions in Cav-3 levels are sufficient to render these mice resistant to tumorigenesis. Thus, Cav-3 (-/-) mice are a novel preclinical model to study the protective effects of a constitutive lactogenic microenviroment on mammary tumor onset and progression. Our current studies have broad implications for using the lactogenic micro-environment as a paradigm to discover new therapies for the prevention and/or treatment of human breast cancers. Most importantly, a lactation-based therapeutic strategy would provide a more natural and nontoxic approach to the development of novel anti-cancer therapies.
Loss of caveolin-3 induces a lactogenic microenvironment that is protective against mammary tumor formation.
No sample metadata fields
View SamplesLoss of function mutations in the SCN9a gene encoding voltage-gated sodium channel Nav1.7 cause congenital insensitivity to pain (CIP) and anosmia in otherwise normal humans and mice, suggesting that this channel may be a good analgesic drug target. Surprisingly, potent selective antagonists of Nav1.7 are weak analgesics. We therefore investigated whether Nav1.7 , as well as contributing to electrical signalling may have an additional function. Here we report that Nav1.7 deletion has profound effects on the sensory neuron transcriptome, leading to dysregulation of a number of transcription factors as well as upregulation of enkephalin precursor PENK mRNA and down regulation of CEACAM10 mRNA, a protein involved in noxious thermosensation. PENK mRNA is transcriptionally upregulated in Nav1.7 null mutant female sensory neurons, resulting in increased enkephalin expression in the dorsal horn of the spinal cord. PENK expression is down-regulated by addition of the sodium ionophore monensin, suggesting that sodium may play a role as a second messenger. Application of the opioid antagonist naloxone strongly enhances noxious peripheral input into the spinal cord, and dramatically reduces analgesia in both male and female Nav1.7 null mutant mice, as well as in human Nav1.7 null mutants. These data show that loss of Nav1.7 expression increases opioid drive over the lifetime of mice and humans. They further suggest that Nav1.7 channel blockers alone may not replicate the phenotype of null mutant humans and mice, but should be potentiated with exogenous opioids.
Endogenous opioids contribute to insensitivity to pain in humans and mice lacking sodium channel Nav1.7.
Specimen part
View SamplesControl of mRNA half-life is a powerful strategy to adjust individual mRNA levels to various stress conditions, because the mRNA degradation rate controls not only the steady-state mRNA level but also the transition speed of mRNA levels. Here, we analyzed mRNA half-life changes in response to cold stress in Arabidopsis cells using genome-wide analysis, in which mRNA half-life measurements and transcriptome analysis were combined. Half-lives of average transcripts were determined to be elongated under cold conditions. Taking this general shift into account, we identified more than a thousand transcripts that were classified as relatively stabilized or relatively destabilized. The relatively stabilized class was predominantly observed in functional categories that included various regulators involved in transcriptional, post-transcriptional and post-translational processes. On the other hand, the relatively destabilized class was enriched in categories related to stress and hormonal response proteins, supporting the idea that rapid decay of mRNA is advanta- geous for swift responses to stress. In addition, pentatricopeptide repeat, cyclin-like F-box and Myb transcription factor protein families were significantly over-represented in the relatively destabilized class. The global analysis presented here demonstrates not only the importance of mRNA turn-over control in the cold stress response but also several structural characteristics that might be important in the control of mRNA stability.
Changes in mRNA stability associated with cold stress in Arabidopsis cells.
Cell line
View SamplesHigh levels of oxidative stress and an associated neuronal DDR occur at the earliest stages of Alzheimer pathology (low Braak stage), and is associated with cognitive impairment.
Neuronal DNA damage response-associated dysregulation of signalling pathways and cholesterol metabolism at the earliest stages of Alzheimer-type pathology.
Specimen part
View SamplesWe examined global gene expression patterns in response to PGC-1 expression in cells derived from liver or muscle.
Direct link between metabolic regulation and the heat-shock response through the transcriptional regulator PGC-1α.
Specimen part
View SamplesCell adhesion plays an important role in determining cell shape and function in a variety of physiological and pathophysiological conditions. While links between metabolism and cell adhesion were previously suggested, the exact context and molecular details of such a cross-talk remain incompletely understood.
Inhibition of Adhesion Molecule Gene Expression and Cell Adhesion by the Metabolic Regulator PGC-1α.
Specimen part, Cell line
View SamplesSecreted proteins serve pivotal roles in the development of multicellular organisms, acting as structural matrix, extracellular enzymes and signal molecules. In this study we demonstrate, unexpectedly, that PGC-1, a critical transcriptional co-activator of metabolic gene expression, functions to down-regulate expression of diverse genes encoding secreted molecules and extracellular matrix (ECM) components to modulate the secretome. We show that both endogenous and exogenous PGC-1 down-regulate expression of numerous genes encoding secreted molecules. Mechanistically, results obtained using mRNA stability measurements as well as intronic RNA expression analysis are consistent with a transcriptional effect of PGC-1 on expression of genes encoding secreted proteins. Interestingly, PGC-1 requires the central heat shock response regulator HSF1 to affect some of its targets, and both factors co-reside on several target genes encoding secreted molecules in cells. Finally, using a mass spectrometric analysis of secreted proteins, we demonstrate that PGC-1 modulates the secretome of mouse embryonic fibroblasts (MEFs).
Control of Secreted Protein Gene Expression and the Mammalian Secretome by the Metabolic Regulator PGC-1α.
Specimen part
View SamplesPlants possess a cold acclimation system to acquire freezing tolerance through pre-exposure to non-freezing low temperatures. The transcriptional cascade of C-repeat binding factors (CBFs)/dehydration response element-binding factors (DREBs) is considered a major transcriptional regulatory pathway during cold acclimation. However, little is known regarding the functional significance of mRNA stability regulation in the response of gene expression to cold stress. The actual level of individual mRNAs is determined by a balance between mRNA synthesis and degradation. Therefore, it is important to assess the regulatory steps to increase our understanding of gene regulation. Here, we analyzed temporal changes in mRNA amounts and half-lives in response to cold stress in Arabidopsis cell cultures based on genome-wide analysis. In this mRNA decay array method, mRNA half-life measurements and microarray analyses were combined. In addition, temporal changes in the integrated value of transcription rates were estimated from the above two parameters using a mathematical approach. Our results showed that several cold-responsive genes, including Cold-regulated 15a, were relatively destabilized, whereas the mRNA amounts were increased during cold treatment by accelerating the transcription rate to overcome the destabilization. Considering the kinetics of mRNA synthesis and degradation, this apparently contradictory result supports that mRNA destabilization is advantageous for the swift increase in CBF-responsive genes in response to cold stress.
Co-ordinated Regulations of mRNA Synthesis and Decay during Cold Acclimation in Arabidopsis Cells.
Cell line
View SamplesPurpose: The objective of this study was to determine cardiac transcriptional pathways regulated in response to 1.) hypothyroidism and re-establishment of a euthyroid state and 2.) Med13-dependent cardiac transcriptional pathways regulated in response to hypothyroidism and re-establishment of a euthyroid state Overall design: Methods: WT and Med13 cardiac-specific knockout mice (Med13cKO) were put on a normal chow or PTU diet at 8 weeks of age for a duration of 4 weeks. A third group was put on a PTU diet for 4 weeks followed by 3 daily injections of T3.
Regulation of cardiac transcription by thyroid hormone and Med13.
No sample metadata fields
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