Project description:Six1, Six4 and Myogenin are transcription factors that are known to be required for skeletal myogenesis. Currently, very little is known about the genes targeted by Six1 and Six4. Gene expression profiling when one or both transcription factors were knock-down by siRNA was performed to identify genes affected by their absence. We also hypothesized that Six1 and Six4 can work in cooperation with the myogenic regulatory factor (MRFs) family of transcription factors, such as Myogenin. Therefore, we performed the same type of experiment where the myogenin was knocked-down by siRNA to identify genes that are possibly regulated by the Six1 or Six4 in conjunction with Myogenin. C2C12 Myoblasts were transfected with siRNA against Six1, Six4, Six1 with Six4, Myogenin, or control 24h before start of differentiation. The cells were allowed to differentiate in differentiation medium for 24h and were harvested for gene expression profiling. Four replicates per siRNA were performed.
Project description:Six1, Six4 and Myogenin are transcription factors that are known to be required for skeletal myogenesis. Currently, very little is known about the genes targeted by Six1 and Six4. Gene expression profiling when one or both transcription factors were knock-down by siRNA was performed to identify genes affected by their absence. We also hypothesized that Six1 and Six4 can work in cooperation with the myogenic regulatory factor (MRFs) family of transcription factors, such as Myogenin. Therefore, we performed the same type of experiment where the myogenin was knocked-down by siRNA to identify genes that are possibly regulated by the Six1 or Six4 in conjunction with Myogenin.
Project description:In this study, the C2C12 cell line, a model used to study myogenesis and regeneration, was allowed to differentiate from myoblast precursor cells to myotubes. Cells were harvested at 3 different timepoints to perform ChIP-on-Chip of Six1, which is a key muscle regulator. We identified global loci bound by Six1 during skeletal myoblast differentiation.
Project description:In this study, the C2C12 cell line, a model used to study myogenesis and regeneration, was allowed to differentiate from myoblast precursor cells to myotubes. Cells were harvested at 3 different timepoints to perform ChIP-on-Chip of Six1, which is a key muscle regulator. We identified global loci bound by Six1 during skeletal myoblast differentiation. C2C12 Myoblasts were allowed to differentiate into myotubes. Cells at three timepoints were harvested for ChIP-on-Chip, including myoblasts stage, 24h after differentiation and myotubes (96h after differentiation). Myotubes were detached from the undifferentiated myoblast reserve cells using diluted trypsin. 3 independent biological replicates were used for each time point experiment. A microarray set counts 3 arrays (Custom Arrays A, B and C) for a total of approximately 2.9 million probes.
Project description:Identification of the gene targets of the SIX transcription factors in myogenic stem cells and in whole back muscles during murine fetal development Pax7 expression marks stem cells in developing skeletal muscles and adult satellite cells during homeostasis and muscle regeneration. The genetic determinants that control the entrance into the myogenic program and the appearance of PAX7+ cells during embryogenesis are poorly understood. SIX homeoproteins are encoded by the Sine oculis homeobox related Six1-Six6 genes in vertebrates. Six1, Six2, Six4 and Six5 are expressed in the muscle lineage. Here we tested the hypothesis that Six1 and Six4 could participate in the genesis of myogenic stem cells. We show that fewer PAX7+ cells occupy a satellite cell position between the myofiber and its associated basal lamina in Six1 and Six4 (s1s4KO) at E18. However, PAX7+ cells are detected in remaining muscle masses present in the epaxial region of the double mutant embryos and are able to divide and contribute to muscle growth. To further characterize the properties of s1s4KO PAX7+ cells, we analyzed their transcriptome and tested their properties after transplantation in adult regenerating tibialis anterior (TA) muscle. Mutant stem cells form hypotrophic myofibers that are not innervated but retain the ability to self-renew.
Project description:The aim of the experiment was to compare the transcriptome of Six1-/-Six4-/- and control embryos in order to identify genes under the control of Six proteins at E18.5. E18.5 RNAs from back muscles of three SixdKO and two control embryos were hybridized on Affymetrix mouse genome 430A2.0 arrays (Affymetrix, Strasbourg - France).
Project description:In this study, we used ChIP-seq to map Six4 binding profile in different C2C12 cell lines 24 hours after differentiation (T24). We performed ChIP-seq using two different antibodies: anti-Flag antibody in Flag-Six4 C2C12 cell line or in parental C2C12 cells; a custom-made anti-Six4 antibody in shNS C2C12 cell line (a control cell line) or shSix4 C2C12 (C2C12 with stable Six4 knockdown using short hairpin RNA). We also performed ChIP-seq in parental C2C12 cells using normal rabbit IgG. We were able to identify Six4-bound loci in C2C12 T24 that were recognized by two different antibodies and showed a decrease in peak intensity in shSix4 C2C12 compared to shNS C2C12 cells. We established a C2C12 cell line with stable Six4 knockdown by short hairpin RNA (shSix4) vs. a control cell line (shNS). We also established a C2C12 cell line with stable expression of Flag-Six4-myc by infection of retroviruses expressing pBABE-Flag-Six4-myc (Flag-Six4 C2C12) vs. parental C2C12. We differentiate these cells for 24 hours before using them for ChIP-seq.
Project description:The aim of the experiment was to compare the transcriptome of Six1-/-Six4-/- and control embryos in order to identify genes under the control of Six proteins at E10.5.<br><br>E10.5 embryos were eviscerated, head and limbs were discarded, the neural tube was removed, and RNAs were prepared with the remaining axial tissues. <br><br>E10.5 RNAs from three SixdKO and two control embryos were hybridized on Affymetrix mouse genome 430A2.0 arrays (Affymetrix, Strasbourg - France).