Influence of LKB1 on contraction-induced gene expression in skeletal muscle
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE72352 | GEO | 2016/01/21
SECONDARY ACCESSION(S): PRJNA293860
REPOSITORIES: GEO
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2020-11-30 | GSE160827 | GEO
Project description:Recent studies indicate that the LKB1 tumour suppressor protein kinase is the major "upstream" activator of the energy sensor AMP-activated protein kinase (AMPK). We have used mice in which LKB1 is expressed at only approximately 10% of the normal levels in muscle and most other tissues, or that lack LKB1 entirely in skeletal muscle. Muscle expressing only 10% of the normal level of LKB1 had significantly reduced phosphorylation and activation of AMPKalpha2. In LKB1-lacking muscle, the basal activity of the AMPKalpha2 isoform was greatly reduced and was not increased by the AMP-mimetic agent, 5-aminoimidazole-4-carboxamide riboside (AICAR), by the antidiabetic drug phenformin, or by muscle contraction. Moreover, phosphorylation of acetyl CoA carboxylase-2, a downstream target of AMPK, was profoundly reduced. Glucose uptake stimulated by AICAR or muscle contraction, but not by insulin, was inhibited in the absence of LKB1. Contraction increased the AMP:ATP ratio to a greater extent in LKB1-deficient muscles than in LKB1-expressing muscles. These studies establish the importance of LKB1 in regulating AMPK activity and cellular energy levels in response to contraction and phenformin.
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Project description:We characterize the phenotype of mice in which the deletion of Lkb1 has been targeted in the liver. Lack of Lkb1 in the liver results in bile duct paucity leading to cholestasis. This phenotype is similar to that obtained upon inactivation of Notch signaling in the liver. We test the hypothesis of a functional overlap between the Lkb1 and Notch pathways by gene expression profiling of livers deficent in Lkb1 or in the Notch mediator RbpJκ. We used AlfpCre mice for liver-specific deletion of LKB1 that were crossed with a conditional knockout mouse model (LKB1 floxed mice). We used also AlfpCre mice for liver-specific inactivation of the Notch pathway. AlfpCre mice were crossed with the RbpJκ floxed mice. RNA was extracted from the liver of LKB1 KO mice (Lkb1Floxed, AlfpCre positive mice) and their wild-type counterpart (Lkb1Floxed, AlfpCre negative mice). RNA was also extracted from liver of RbpJK KO mice (RbpJK floxed, AlfpCre positive) and their wild type mice (RbpJK floxed, AlfpCe negative). 6 samples for the liver-specific deletion of LKB1 corresponding to 3 KO LKB1 (Cre positive) and 3 normal liver (Cre negative). 6 samples for the liver-specific inactivation of the Notch pathway corresponding to 3 KO RbpJk (Cre positive) and 3 normal liver (Cre negative).
2015-12-08 | E-GEOD-75564 | biostudies-arrayexpress
Project description:Fast skeletal myosin binding protein-C regulates fast skeletal muscle contraction
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Project description:We characterize the phenotype of mice in which the deletion of Lkb1 has been targeted in the liver. Lack of Lkb1 in the liver results in bile duct paucity leading to cholestasis. This phenotype is similar to that obtained upon inactivation of Notch signaling in the liver. We test the hypothesis of a functional overlap between the Lkb1 and Notch pathways by gene expression profiling of livers deficent in Lkb1 or in the Notch mediator RbpJκ. We used AlfpCre mice for liver-specific deletion of LKB1 that were crossed with a conditional knockout mouse model (LKB1 floxed mice). We used also AlfpCre mice for liver-specific inactivation of the Notch pathway. AlfpCre mice were crossed with the RbpJκ floxed mice. RNA was extracted from the liver of LKB1 KO mice (Lkb1Floxed, AlfpCre positive mice) and their wild-type counterpart (Lkb1Floxed, AlfpCre negative mice). RNA was also extracted from liver of RbpJK KO mice (RbpJK floxed, AlfpCre positive) and their wild type mice (RbpJK floxed, AlfpCe negative).
2015-12-08 | GSE75564 | GEO
Project description:Common acute injuries to skeletal muscle can lead to significant pain and disability. The current therapeutic approaches for treating muscle injuries are dependent on the clinical severity but not on the type of injury. The aim of this study was to compare the molecular events accompanying the degeneration and repair phases of contraction- and trauma-induced muscle injuries by applying DNA microarray methodology to two well-characterized mouse models of skeletal muscle injury, i.e., eccentric contraction-induced injury (CI) and traumatic injury induced by freezing (FI). Histopathological evaluation and measurements of muscle strength were accompanied by analyses of expression for 12,488 known genes at four time points ranging from 6 hours to 7 days post-injury. Real-time RT-PCR was used to confirm some of the gene expression temporal profiles. While both types of injury cause early induction of transcription, myogenic, and stress-responsive factors, they also induce injury type-specific gene expression profiles. CI only activates a set of genes associated with the protection and repair of protein and structural integrity while FI activates gene sets which result in extensive inflammatory responses, tissue remodeling, angiogenesis, and myofibre and extracellular matrix synthesis. This study identified genes that are candidates for therapeutic manipulation following two disparate types of muscle injury. Keywords: time course, comparative genomic hybridization
2006-12-31 | GSE5413 | GEO
Project description:Liver kinase B1 (LKB1) is a tumor-suppressing protein that is involved in the regulation of muscle metabolism and growth by phosphorylating and activating AMP-activated protein kinase (AMPK) family members. Here we report the development of a myopathic phenotype in skeletal and cardiac muscle-specific LKB1 knockout (mLKB1-KO) mice. The myopathic phenotype becomes overtly apparent at 30-50 wk of age and is characterized by decreased body weight and a proportional reduction in fast-twitch skeletal muscle weight. The ability to ambulate is compromised with an often complete loss of hindlimb function. Skeletal muscle atrophy is associated with a 50-75% reduction in mammalian target of rapamycin pathway phosphorylation, as well as lower peroxisome proliferator-activated receptor-alpha coactivator-1 content and cAMP response element binding protein phosphorylation (43 and 40% lower in mLKB1-KO mice, respectively). Maximum in situ specific force production is not affected, but fatigue is exaggerated, and relaxation kinetics are slowed in the myopathic mice. The increased fatigue is associated with a 30-78% decrease in mitochondrial protein content, a shift away from type IIA/D toward type IIB muscle fibers, and a tendency (P=0.07) for decreased capillarity in mLKB1-KO muscles. Hearts from myopathic mLKB1-KO mice exhibit grossly dilated atria, suggesting cardiac insufficiency and heart failure, which likely contributes to the phenotype. These findings indicate that LKB1 plays a critical role in the maintenance of both skeletal and cardiac function.
| S-EPMC2886679 | biostudies-literature
Project description:Gene expression in wildtype mouse stomach wall (n=6), Lkb1+/- mouse stomach wall (n=6) and Lkb1+/- mouse gastric polyps
2010-10-06 | E-MEXP-2444 | biostudies-arrayexpress
Project description:Inherited mutation in LKB1 results in the Peutz-Jeghers syndrome (PJS), characterized by intestinal hamartomas and a modestly increased frequency of gastrointestinal and breast cancer1. Somatic inactivation of LKB1 occurs in human lung adenocarcinoma2-4, but its tumor suppressor role in this tissue is unknown. Here we show that somatic Lkb1 deficiency strongly cooperates with somatic K-rasG12D activating mutation to accelerate the development of mouse lung tumorigenesis. Lkb1 deficiency in the setting of K-rasG12D mutation (K-ras Lkb1L/L) was associated with decreased tumor latency and increased tumor aggressiveness including metastasis. Furthermore, tumors from K-ras Lkb1L/L mice demonstrated histologies--squamous, adenosquamous and large cell--not seen with K-rasG12D mutation, Ink4a/Arf inactivation, or p53 inactivation alone or in combination. Experiments in vitro suggest that LKB1 suppresses lung tumorigenesis and progression through both p16INK4a-ARF-p53 dependent and independent mechanisms. These data indicate that LKB1 regulates lung tumor progression and differentiation. Keywords: cancer research To analyze the role of LKB1 in lung cancer progression and differentiation, we have dissected the lung tumors from mice with/without lkb1 loss and performed the microarray analyses to compare their gene expression pattern. In addition, we have also performed microarray analysis in both A549 and H2126 cell lines after reconsistitution of either wt-lkb1 or the kinase dead form of lkb1 (lkb1-KD) to confirm what we observed from in vivo studies.
2007-08-28 | E-GEOD-6135 | biostudies-arrayexpress
Project description:To begin to validate potential causal regulators of muscle function, we targeted genes containing novel skeletal muscle pQTLs and molecular/phenotypic associations, and performed a functional genomic screen in human skeletal muscle organoids (PMID: 30527761). We focused on proteins with negative associations to lean mass, grip strength or other metabolic associations, and generated a total of 27 individual rAAV6:shRNAs. Organoids were grown around contraction posts to monitor contractile force production during electrical stimulation, and transduced following differentiation and maturation to limit effects on the myogenic program (Figure 3A). Electrical stimulation was performed to induce either a tetanic contraction for assessment of maximum force production or stimulated with sustained lower frequency for assessment of fatigue. Following the protocol, organoids were analysed by proteomics which quantified 17/27 targets with 13 targets significantly reduced in abundance by rAAV6:shRNA.
2023-01-08 | PXD034913 | Pride