Down-regulation of JunB by RNAi in mouse muscles in vivo
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE18664 | GEO | 2010/01/01
SECONDARY ACCESSION(S): PRJNA121529
REPOSITORIES: GEO
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2016-07-15 | E-GEOD-67069 | biostudies-arrayexpress
Project description:For additional details see Bongers et al, Spermine Oxidase Maintains Basal Skeletal Muscle Gene Expression and Fiber Size, and Is Strongly Repressed by Conditions that Cause Skeletal Muscle Atrophy . Am J Physiol Endocrinol Metab. 2014 [under review] Bilateral tibialis anterior muscles of C57BL/6 mice were harvested seven days after transfection with p21 or control plasmid.
2014-12-04 | E-GEOD-63007 | biostudies-arrayexpress
Project description:For additional details see Bongers et al, Spermine Oxidase Maintains Basal Skeletal Muscle Gene Expression and Fiber Size, and Is Strongly Repressed by Conditions that Cause Skeletal Muscle Atrophy . Am J Physiol Endocrinol Metab. 2014 [under review] Bilateral tibialis anterior muscles of C57BL/6 mice were harvested seven days after transfection with spermine oxidase or control plasmid.
2014-12-04 | E-GEOD-63006 | biostudies-arrayexpress
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2015-12-11 | E-GEOD-68915 | biostudies-arrayexpress
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2013-09-17 | E-GEOD-49826 | biostudies-arrayexpress
Project description:Skeletal muscle atrophy is a serious and highly prevalent condition that remains poorly understood at the molecular level. Previous work found that skeletal muscle atrophy involves an increase in skeletal muscle Gadd45a expression, which is necessary and sufficient for skeletal muscle fiber atrophy. However, the direct mechanism by which Gadd45a promotes skeletal muscle atrophy was unknown. To address this question, we biochemically isolated skeletal muscle fiber proteins that associate with Gadd45a as it induces skeletal muscle atrophy in living mice. We found that Gadd45a interacts with multiple proteins in skeletal muscle fibers, including, most prominently, the MAP kinase kinase kinase MEKK4. Furthermore, by forming a complex with MEKK4 in skeletal muscle fibers, Gadd45a increases MEKK4 protein kinase activity, which is sufficient to induce skeletal muscle fiber atrophy and required for Gadd45a-mediated skeletal muscle fiber atrophy. Together, these results identify a direct biochemical mechanism by which Gadd45a induces skeletal muscle atrophy and provide new insight into way that skeletal muscle atrophy occurs at the molecular level.
2016-05-17 | MSV000079730 | MassIVE
Project description:Under stress conditions mammalian cells activate compensatory mechanisms to survive and maintain cellular function. During catabolic conditions, such as low nutrients, systemic inflammation, cancer or infections, protein breakdown is enhanced and aminoacids are released from muscles to sustain liver gluconeogenesis and tissues protein synthesis. Proteolysis in muscle is orchestrated by a set of genes named atrophy-related genes. A system that is activated both in short and prolonged stress conditions is the family of Forkhead Box (Fox) O transcription factors. Here, we report that muscle-specific deletion of FoxO members resulted in protection from muscle loss because FoxO family is required for induction of autophagy-lysosome and ubiquitin-proteasome systems. Importantly, FoxOs are required for Akt activity but not for mTOR signalling underlining the concept that FoxOs are upstream mTOR for the control of protein breakdown when nutrients are lacking. Moreover, FoxO family controls the induction of critical genes belonging to several fundamental stress response pathways such as unfolded protein response, ROS detoxification and translational regulation. Finally, we identify a set of novel FoxO-dependent ubiquitin ligases including the recent discovered MUSA11 and a new one, which we named Specific of Muscle Atrophy and Regulated by Transcription (SMART). Our findings identify the critical role of FoxO in regulating a variety of genes belonging to pathways important for stress-response under catabolic conditions. Gene expression in muscles of muscle-specific FoxO 1,3,4 knock-out mice that were fed normally or starved We generated knocked-out FoxO 1,3,4 specifically in muscle by crossing FoxO1-3-4-floxed mice (FoxO1,3,4 f/f) with a transgenic line expressing Cre recombinase under the control of MLC1f promoter to generate muscle-specific FoxO1,3,4 triple knockout mice. These mice were either fed ad libitum or starved. Subsequently gene expression of the gastrocnemius muscles was analyzed. For each of the 4 conditions (FOXO1,3,4 f/f fed or starved, FOXO1,3,4-/- fed or starved), we isolated the gastrocnemius muscles of 3 mice thus yielding 6 muscles per condition. RNA was prepared from these muscles using the TRIzol method (Life Technologies) followed by cleanup with the RNeasy kit (QIAGEN). RNA concentration was determined by spectrophotometry and quality of the RNA was monitored using the Agilent 2100 Bioanalyzer (Agilent Technologies). RNA of the 6 muscles per condition was pooled equimolarly and used for further microarray analysis. cRNA was prepared, labelled and hybridised to Affymetrix Mouse Genome 430 2.0 Arrays using Affymetrix-supplied kits and according to standard Affymetrix protocols. Expression values were summarized using the Mas 5.0 algorithm. Genes that were up- or downregulated upon starvation compared to the fed condition were determined using Excel software. A threshold of 1.5 was used for the fold up-or downregulation consistent with the fold change that can be reliably detected with these type of arrays.
2015-04-24 | E-GEOD-52667 | biostudies-arrayexpress
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Project description:Skeletal muscle atrophy is a consequence of many diseases, environmental insults, inactivity, age and injury. Atrophy is characterized by active degradation and removal of contractile proteins and a reduction in fiber size. Animal models have been extensively used to identify pathways leading to atrophic conditions. Here we have used genome-wide expression profiling analysis and quantitative PCR to identify the molecular changes that occur in two clinically relevant animal mouse models of muscle atrophy, hindlimb casting and Achilles tendon laceration (tenotomy). Gastrocnemius muscle samples were collected 2, 7 and 14 days after insult. The total amount of muscle loss as measured by wet weight and muscle fiber size was equivalent between models, although tenotomy resulted in a more rapid induction of muscle atrophy. Furthermore, tentomy resulted in the regulation of significantly more mRNA transcripts then casting. Analysis of the regulated genes and pathways suggest that the mechanism of atrophy is distinct between these models. The degradation following casting appears ubiquitin-proteasome-mediated while degradation following tenotomy appears lysosomal and matrix-metalloproteinase (MMP)-mediated. This data suggests that there are multiple mechanisms leading to muscle atrophy and that specific therapeutic agents may be necessary to combat the atrophy seen under different conditions. Muscle atrophy was induced through two methods; unloading induced by tendon laceration (Tenotomy) and immobilization induced by hindlimb casting (Casting). For the tenotomy, eight week old male C57/B6 mice were anesthetized by ether inhalation and subsequent intramuscular injection of ketamine-xylazine (0.1 ml/g). The right Achilles tendon just proximal to the calcaneus was severed with a sterile scalpel. The mice were allowed to recover and move freely about their cage. An additional cohort of animals was sham operated (Sham) which involved isolation and manipulation of the Achilles tendon without laceration. For the casting, the right hindlimbs of eight week old male C57Bl/6 mice were immobilized through casting. After 2, 7 or 14 days, animals were sacrificed and the left and right gastrocnemius muscles were carefully removed, flash frozen in liquid nitrogen, and stored at -80°C for further processing. The left untreated legs served as controls. A group of naïve animals that received no treatment or manipulation was included as an additional control. Each group consisted of between 5 and 10 samples for a total of 111 individual samples.
2011-10-24 | E-GEOD-25908 | biostudies-arrayexpress