Project description:Background: MicroRNAs (miRNAs) are a family of small, non-coding single-stranded RNA molecules involved in post-transcriptional regulation of gene expression. As such, they are believed to play a role in regulating the step-wise changes in gene expression patterns that occur during cell fate specification of multipotent stem cells. Here, we have studied whether terminal differentiation of C2C12 myoblasts is indeed controlled by lineage-specific changes in miRNA expression. Results: Using a previously generated RNA polymerase II (Pol-II) ChIP-on-chip dataset, we show differential Pol-II occupancy at the promoter regions of six miRNAs during C2C12 myogenic versus BMP2-induced osteogenic differentiation. Overexpression of one of these miRNAs, miR-378, enhances Alp activity, calcium deposition and mRNA expression of osteogenic marker genes in the presence of BMP2. Conclusions: Our results demonstrate a previously unknown role for miR-378 in promoting BMP2-induced osteogenic differentiation. Stable C2C12 cell lines C2C12-pMirn0 and C2C12-pMirn378 were generated by lentiviral transduction of C2C12 myoblasts with a Mirn378-overexpression construct and its parent vector, respectively. C2C12-pMirn0 and C2C12-pMirn378 cells were plated at 2.5 x 10^4 cells/cm2 (day -1), cultured for 1 day in DMEM 10%NCS, then (d0) treated with or without 300 ng/ml bone morphogenetic protein 2 (BMP2) for 6 days. RNA was extracted on d0, d3 and d6 and hybridized to GeneChip Mouse Genome 430 2.0 array (Affymetrix).
Project description:Background: MicroRNAs (miRNAs) are a family of small, non-coding single-stranded RNA molecules involved in post-transcriptional regulation of gene expression. As such, they are believed to play a role in regulating the step-wise changes in gene expression patterns that occur during cell fate specification of multipotent stem cells. Here, we have studied whether terminal differentiation of C2C12 myoblasts is indeed controlled by lineage-specific changes in miRNA expression. Results: Using a previously generated RNA polymerase II (Pol-II) ChIP-on-chip dataset, we show differential Pol-II occupancy at the promoter regions of six miRNAs during C2C12 myogenic versus BMP2-induced osteogenic differentiation. Overexpression of one of these miRNAs, miR-378, enhances Alp activity, calcium deposition and mRNA expression of osteogenic marker genes in the presence of BMP2. Conclusions: Our results demonstrate a previously unknown role for miR-378 in promoting BMP2-induced osteogenic differentiation.
Project description:Bone morphogenetic proteins (BMPs) regulate many aspects of skeletal development, including osteoblast and chondrocyte differentiation, cartilage and bone formation, and cranial and limb development. Among them, BMP2, one of the most potent osteogenic signaling molecules, stimulates osteoblast differentiation, while it inhibits myogenic differentiation in C2C12 cells. We used cDNA microarrays to elucidate regulators of BMP-2-induced osteoblast differentiation.
Project description:Bone morphogenetic proteins (BMPs) regulate many aspects of skeletal development, including osteoblast and chondrocyte differentiation, cartilage and bone formation, and cranial and limb development. Among them, BMP2, one of the most potent osteogenic signaling molecules, stimulates osteoblast differentiation, while it inhibits myogenic differentiation in C2C12 cells.
Project description:Reconstruction of bone defects and compensation of deficient repair mechanisms represent important goals within the field of regenerative medicine and require novel safe strategies for translation into the clinic. Therefore, we generated a nonviral osteogenic gene therapeutic (hybrid) vector system, combining an improved bone morphogenetic protein 2 (BMP2) gene cassette and pro-osteogenic microRNAs. The hybrid vectors were tested for their functionality and osteogenic differentiation potential in C2C12 and C3H/10T1/2 via alkaline phosphatase enzyme activity assay, enzyme-linked immunosorbent assay and reverse transcription quantitative polymerase chain reaction analysis of miRNA and osteogenic marker expression. In a mouse ectopic bone formation model, osteoinduction in transfected muscle tissue was analysed via micro computed tomography scans and histological staining. All tested hybrid vector systems led to an increase in BMP2 protein overexpression in C2C12 and C3H/10T1/2, when compared with miRNA-lacking constructs. Incorporated miRNAs were found to be efficiently upregulated. Distinct intra- and extracellular localization preferences were observed. The hybrid vector consisting of BMP2 and miR-590 revealed highest potential of inducing osteogenic differentiation. The favourable effect of combining overexpression of BMP2 and miRNAs has been shown in vitro and in vivo. Induction of mineralization was observed in an ectopic bone mouse model, although high variability in terms of size and shape indicates potential for improvement regarding plasmid administration and retention. We believe this study contributes in a valuable way to the preclinical knowledge of nonviral gene therapy for tissue regeneration. Also, we hope to encourage additional research on multi-target gene therapeutic approaches.
Project description:KSRP knock-down and BMP2 treatment produce a largely overlapping reshape of the transcriptome in C2C12 cells. microRNAs (miRNAs) are essential regulators of development, physiology, and evolution with miRNA biogenesis being strictly controlled at multiple levels. Regulatory proteins, such as KH-type splicing regulatory protein (KSRP), modulate rates and timing of the enzymatic reactions responsible for maturation of select miRNAs from their primary transcripts in response to specific stimuli. Induction of myogenic miRNAs (myomiRs) is essential for muscle differentiation with KSRP phosphorylation being required to convey myogenic signals to enhanced myomiR maturation. Here we show that either KSRP silencing or Bone Morphogenetic Protein (BMP)2-signaling activation in mesenchimal C2C12 cells prevented myogenic differentiation while induced osteoblastic differentiation as revealed by the reshaping of the whole transcriptome analyzed by RNA deep-sequencing. The most striking feature common to both BMP2 signaling activation and KSRP silencing was a blockade of myomiR maturation. Our results demonstrate that phosphorylated SMAD proteins, the transducers of BMP signaling, associate with KSRP and block its interaction with primary-myomiRs. This, in turn, abrogates KSRP-dependent myomiR maturation with the knock-down of SMAD4, 5, and 9 being able to rescue KSRP function. SMAD-induced blockade of KSRP-dependent myomiR maturation, in parallel to the well known SMAD function on gene transcription, inhibits C2C12 cell differentiation into myofibers and contributes to orient cells towards osteoblast lineage. We propose that remodeling of co-regulatory complexes affecting primary-miRNA processing is a mechanism well suited to guide cell fate determination in eukaryotes. Total RNA was prepared from 1. untreated mock-transfected C2C12 cells; 2. BMP2-treated mock-transfected C2C12 cells; 3. untreated shKSRP-transfected C2C12 cells and analyzed by RNA-seq
Project description:During fundamental proteotranscriptomic analysis of human valve interstitial cells (VICs) osteogenic differentiation, we revealed ZBTB16 (PLZF) as one of the most upregulated proteins. Thus, to investigate its physiological role in VICs osteogenic differentiation we performed its overexpression by lentiviral transduction with subsequent proteomics analysis. Despite obvious PLZF overexpression and its reinforcing effect on osteogenic differentiation, we revealed surprisingly small amount of differentially expressed proteins that assumed to be the targets of PLZF.
Project description:KSRP knock-down and BMP2 treatment produce a largely overlapping reshape of the transcriptome in C2C12 cells. microRNAs (miRNAs) are essential regulators of development, physiology, and evolution with miRNA biogenesis being strictly controlled at multiple levels. Regulatory proteins, such as KH-type splicing regulatory protein (KSRP), modulate rates and timing of the enzymatic reactions responsible for maturation of select miRNAs from their primary transcripts in response to specific stimuli. Induction of myogenic miRNAs (myomiRs) is essential for muscle differentiation with KSRP phosphorylation being required to convey myogenic signals to enhanced myomiR maturation. Here we show that either KSRP silencing or Bone Morphogenetic Protein (BMP)2-signaling activation in mesenchimal C2C12 cells prevented myogenic differentiation while induced osteoblastic differentiation as revealed by the reshaping of the whole transcriptome analyzed by RNA deep-sequencing. The most striking feature common to both BMP2 signaling activation and KSRP silencing was a blockade of myomiR maturation. Our results demonstrate that phosphorylated SMAD proteins, the transducers of BMP signaling, associate with KSRP and block its interaction with primary-myomiRs. This, in turn, abrogates KSRP-dependent myomiR maturation with the knock-down of SMAD4, 5, and 9 being able to rescue KSRP function. SMAD-induced blockade of KSRP-dependent myomiR maturation, in parallel to the well known SMAD function on gene transcription, inhibits C2C12 cell differentiation into myofibers and contributes to orient cells towards osteoblast lineage. We propose that remodeling of co-regulatory complexes affecting primary-miRNA processing is a mechanism well suited to guide cell fate determination in eukaryotes.