Project description:Long term glucocorticoïds treatment, e.g. corticosterone, induces insulin resistance in vivo and in vitro. In vivo insulin resistance can trigger pancreatic beta cells adaptation in order to maintain glycemia. In particular, we observed that beta-cell mass adaptation can occur via beta-cell proliferation or via beta-cell neogenesis (de novo beta-cell production). Further, we demonstrated that beta-cell neogenesis was not a direct effect of GC, but rather due to the presence of pro-neogenic factors in the serum of GC-treated mice, suggesting a communication in-between insulin resistant tissues and the pancreas (Courty et al., Diabetes, 2019). Hence, the present work aims to decipher the role of the skeletal muscle in pancreatic adaptation in response to insulin resistance. We used an in vitro modeling in-between C2C12 differentiated myotubes treated for 24h with corticosterone (10-7M) or the same volume of solvant ethanol (VEH). Conditioned medium from corticosterone treated cells was tested on pancreatic buds E11.5 and proven to enhance beta-cell and other pro-endocrine lineage cellular differentiation in comparison to VEH conditioned medium. Subsequently, we analyzed the transcriptome of the C2C12 myotubes (n=3 per condition) using RNAsequencing (Illumina, NOVAseq 6000, 150bp paired-end sequencing). We found an enrichement for genes coding for secreted proteins in the CORT-treated myotubes. We narrowed down to 4 myokines candidates and validated the pro-neogenic potential of the candidate myokines using pancreatic buds E11.5 treated with recombinant proteins.
Project description:Maps of genomic regions in proximity to the nuclear lamina were determined in undifferentiated C2C12 myoblasts (MBs) and 6 day differentiated C2C12 myotubes (MTs) using DamID with a Dam-Lamin B1-encoding lentivirus.
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).
Project description:Comparison of undifferentiated C2C12 myoblast to 4 day differentiated myotubes. Experiment Overall Design: this experiment include 2 samples and 6 replicates
Project description:Proliferating C2C12 myoblasts were induced to differentiate into myotubes and then infected with adenovirus expressing E1A (Ad-E1A), which induces cell cycle re-entry and dedifferentiation. We analyzed the transcriptional profile of E1A infected C2C12-myotubes through the Affymetrix Mouse Genome 430 2.0 Array, searching for genes that were significantly regulated between two independent biological replicates at two different time points (24h and 36h after infection with Ad-E1A). In addition, we took advantage of the E1A mutant known as YH47/dl928 (hereafter referred as YH47), which bears two mutations in the pocket-binding region of E1A (Y48H, C124G) able to disrupt the interaction with Rb and its cognate proteins and to impair cell-cycle re-entry phenotype. YH47 mutant was used to identify the Rb independent transcriptional reprogramming of C2C12. C2C12 cells were differentiated in vitro to myotubes as previously described. Myotubes were, then, infected with an adenovirus carrying the 12S form of E1A (dl520), with the YH47 E1A mutant (dl928) or with a control adenovirus (CTR) expressing a deletion of essentially the entire E1A gene (dl312). Two different time points after infection were considered (24 hours and 36 hours) to evaluate changes in C2C12 cells expression profile. Technical (A or B) and biological replicates (EXP1 or EXP2) were done for each condition.
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
Project description:Prion infection in animals results in neurodegeneration and eventually death. To examine the cellular impact of Prion disease, we profiled non-proliferative fully differentiated C2C12 cells, which can replicate prions to high levels. Results suggest that accumulation of high levels of PrPSc in C2C12 myotubes does not cause any overt cellular dysfunction or molecular pathology. C2C12 cells were differentiated into confluent myotubes. Cells were infected or not with 100ul of 10% brain homogenate obtained from a C57BL/6 mouse clinically affected with RML prions. 16 days after infection, cells were collected by scraping and RML was purified.
Project description:Proliferating C2C12 myoblasts were induced to differentiate into myotubes and then infected with adenovirus expressing E1A (Ad-E1A), which induces cell cycle re-entry and dedifferentiation. We analyzed the transcriptional profile of E1A infected C2C12-myotubes through the Affymetrix Mouse Genome 430 2.0 Array, searching for genes that were significantly regulated between two independent biological replicates at two different time points (24h and 36h after infection with Ad-E1A). In addition, we took advantage of the E1A mutant known as YH47/dl928 (hereafter referred as YH47), which bears two mutations in the pocket-binding region of E1A (Y48H, C124G) able to disrupt the interaction with Rb and its cognate proteins and to impair cell-cycle re-entry phenotype. YH47 mutant was used to identify the Rb independent transcriptional reprogramming of C2C12.
Project description:To determine the circRNA expression profile in C2C12 myoblasts and myotubes, we used mouse circRNA microarray from Arraystar to examine the expression of circRNAs in C2C12 myoblasts and myotubes.
Project description:To determine the lncRNA expression profile in C2C12 myoblasts and myotubes, we used mouse lncRNA microarray from Arraystar to examine the expression of lncRNAs in C2C12 myoblasts and myotubes.