Ontology highlight
ABSTRACT:
PROVIDER: PRJNA124353 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Fasting increases the level of skeletal muscle ATF4 mRNA, which promotes skeletal myofiber atrophy. To begin to determine the mechanism of ATF4-mediated myofiber atrophy, we compared the effects of fasting and ATF4 overexpression on global skeletal muscle mRNA expression in C57BL/6 mice.
2010-01-30 | GSE20101 | GEO
Project description:Fasting increases the level of skeletal muscle ATF4 mRNA, which promotes skeletal myofiber atrophy. To begin to determine the mechanism of ATF4-mediated myofiber atrophy, we compared the effects of fasting and ATF4 overexpression on global skeletal muscle mRNA expression in C57BL/6 mice.
2010-01-30 | GSE20103 | GEO
Project description:Skeletal muscle atrophy is a highly prevalent and debilitating condition that remains poorly understood at the molecular level. Previous work found that skeletal muscle atrophy involves activating transcription factor 4 (ATF4), a protein in the basic leucine zipper (bZIP) transcription factor family. However, the direct biochemical mechanism by which ATF4 promotes muscle atrophy was unknown. Because bZIP proteins such as ATF4 must dimerize to bind and activate genes, and because ATF4 is unable to form highly stable homodimers, we hypothesized that ATF4 may promote muscle atrophy by heterodimerizing with another bZIP family member. To test this hypothesis, we biochemically isolated skeletal muscle proteins that associate with the dimerization- and DNA-binding domain of ATF4 (the bZIP domain) in mouse skeletal muscle fibers in vivo. Interestingly, we found that ATF4 makes up one half of at least 5 distinct heterodimeric bZIP transcription factors in skeletal muscle fibers. This three-way interaction between ATF4, C/EBPbeta and the ATF4-C/EBP composite site activates the Gadd45a gene, which encodes a known mediator of muscle atrophy (Gadd45a). Together, these results identify a direct biochemical mechanism by which ATF4 induces skeletal muscle atrophy and provide new insight into the way that skeletal muscle atrophy occurs at the molecular level.
2019-11-04 | MSV000084538 | MassIVE
Project description:ATF4 is a bZIP transcription factor that that promotes skeletal muscle atrophy. The goal of these studies was to determine the effects of ATF4 overexpression on mRNA levels in differentiated C2C12 myotubes. For additional details see Ebert et al, Stress-Induced Skeletal Muscle Gadd45a Expression Reprograms Myonuclei and Causes Muscle Atrophy. JBC epub. June 12,2012 C2C12 myotubes were infected with adenovirus co-expressing eGFP and ATF4-FLAG. Control myotubes were infected with adenovirus co-expressing eGFP and a transcriptionally inactive ATF4 construct (ATF4∆bZIP).
2012-09-15 | E-GEOD-39194 | biostudies-arrayexpress
Project description:ATF4 is a fasting-induced trascription factor that promotes skeletal muscle atrophy. The goal of these studies was to determine how of loss of ATF4 affects skeletal muscle mRNA expression. For additional details see Ebert et al, Stress-Induced Skeletal Muscle Gadd45a Expression Reprograms Myonuclei and Causes Muscle Atrophy. JBC epub. June 12, 2012. Muscle-specfic ATF4 knockout (ATF4 mKO) mice and littermate controls were fasted for 24 hours and then tibialis anterior muscles were harvested. mRNA levels in ATF4 mKO muscles were normalized to levels in littermate control muscles.
2012-09-15 | E-GEOD-39193 | biostudies-arrayexpress
Project description:For additional details see Ebert et al, Identification and Small Molecule Inhibition of an ATF4-dependent Pathway to Age-related Skeletal Muscle Weakness and Atrophy. Quadriceps femoris muscles were harvested from 22-month-old muscle-specfic ATF4 knockout (ATF4 mKO) mice and littermate controls. mRNA levels in ATF4 mKO muscles were normalized to levels in littermate control muscles.
2015-09-03 | E-GEOD-72658 | biostudies-arrayexpress
Project description:AQM shows acute muscle wasting and weakness. Key aspects of AQM include muscle atrophy and myofilament loss. Gene expression profiling, using muscle biopsies from AQM, neurogenic atrophy and normal controls, showed that both myogenic and neurogenic atrophy share induction of myofiber-specific ubiquitin/proteosome pathways while only the AQM shows a specific strong induction of transforming growth factor (TGF)-beta/MAPK pathways.
2007-07-21 | E-GEOD-1017 | biostudies-arrayexpress
Project description:Decline in skeletal muscle cell size (myofiber atrophy) is a key feature of cancer-induced wasting (cachexia). In particular, atrophy of the diaphragm, the major muscle responsible for breathing, is an important determinant of cancer-associated mortality. However, therapeutic options are limited. Here, we have used Drosophila transgenic screening to identify muscle-secreted factors (myokines) that act as paracrine regulators of myofiber growth. Subsequent testing in mouse myotubes revealed that mouse Fibcd1 is an evolutionary-conserved myokine that preserves myofiber size via ERK signaling. Local administration of recombinant Fibcd1 (rFibcd1) ameliorates cachexia-induced myofiber atrophy in the diaphragm of mice bearing patient-derived melanoma xenografts and LLC carcinomas. Moreover, rFibcd1 impedes cachexia-associated transcriptional changes in the diaphragm. Fibcd1-induced signaling appears to be muscle selective because rFibcd1 increases ERK activity in myotubes but not in several cancer cell lines tested. We propose that rFibcd1 may help reinstate myofiber size in the diaphragm of patients with cancer cachexia.
2022-02-28 | GSE158581 | GEO
Project description:Decline in skeletal muscle cell size (myofiber atrophy) is a key feature of cancer-induced wasting (cachexia). In particular, atrophy of the diaphragm, the major muscle responsible for breathing, is an important determinant of cancer-associated mortality. However, therapeutic options are limited. Here, we have used Drosophila transgenic screening to identify muscle-secreted factors (myokines) that act as paracrine regulators of myofiber growth. Subsequent testing in mouse myotubes revealed that mouse Fibcd1 is an evolutionary-conserved myokine that preserves myofiber size via ERK signaling. Local administration of recombinant Fibcd1 (rFibcd1) ameliorates cachexia-induced myofiber atrophy in the diaphragm of mice bearing patient-derived melanoma xenografts and LLC carcinomas. Moreover, rFibcd1 impedes cachexia-associated transcriptional changes in the diaphragm. Fibcd1-induced signaling appears to be muscle selective because rFibcd1 increases ERK activity in myotubes but not in several cancer cell lines tested. We propose that rFibcd1 may help reinstate myofiber size in the diaphragm of patients with cancer cachexia.
2022-02-28 | GSE156815 | GEO
Project description:Myofiber atrophy occurs with aging and in many diseases but the underlying mechanisms are incompletely understood. Here, we have used >1,100 muscle-targeted RNAi interventions to comprehensively assess the function of 447 transcription factors in the developmental growth of body wall skeletal muscles in Drosophila. This screen identifies new regulators of myofiber atrophy and hypertrophy, including the transcription factor Deaf1. Deaf1 RNAi increases myofiber size whereas Deaf1 overexpression induces atrophy. Consistent with its annotation as a Gsk3 phosphorylation substrate, Deaf1 and Gsk3 induce largely overlapping transcriptional changes that are opposed by Deaf1 RNAi. The top category of Deaf1-regulated genes consists of glycolytic enzymes, which are suppressed by Deaf1 and Gsk3 but are upregulated by Deaf1 RNAi. Similar to Deaf1 and Gsk3 overexpression, RNAi for glycolytic enzymes reduces myofiber growth. Altogether, this study defines the repertoire of transcription factors that regulate developmental myofiber growth and the role of Gsk3/Deaf1/glycolysis in this process.
2021-12-10 | GSE174637 | GEO