Regulation of avian fibroblast growth factor receptor 1 (FGFR-1) gene expression during skeletal muscle differentiation

Patel, Suketu G; Funk, Phillip E.; DiMario, Joseph X.

doi:10.1016/s0378-1119(99)00278-4

Cited by 23 publications

(41 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…containing the full-length promoter was described previously (5). A series of mutations was made in the proximal promoter region by utilizing QuikChange site-directed mutagenesis kit (Stratagene) with each of the following forward primers and their antisense oligonucleotides as reverse primers:…”

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

“…Transfected myoblasts and myotubes were harvested 24 h and 9 days after transfection, respectively, and suspended in 100 l of 0.25 M Tris-HCl, pH 7.8. Cells were lysed by three rounds of freezing and thawing, and the CAT assays were performed as described previously (5). Resulting thin layer chromatography plates were then cut and quantified by liquid scintillation counting.…”

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

“…After transfection, cells were maintained in growth medium. Cells were harvested 48 h after transfection, and CAT assays were performed (5). For all transfection assays, four or five independent experiments were performed.…”

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

“…However, FGF signaling declines during myoblast differentiation. This decline is the result of loss of cell surface receptor and a coordinate decrease in FGFR1 mRNA (3)(4)(5).…”

mentioning

confidence: 99%

“…Our previous work on the FGFR1 promoter demonstrated that the promoter was structurally and functionally divided into proximal and distal regions. The distal region is located more than 1 kb upstream from the start of transcription and positively regulates FGFR1 gene expression in myoblasts (5). The distal region contains two Sp transcription factor binding sites, both of which are required for FGFR1 promoter activity in proliferating myoblasts.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Sp1- and Sp3-mediated Transcriptional Regulation of the Fibroblast Growth Factor Receptor 1 Gene in Chicken Skeletal Muscle Cells

Parakati

DiMario

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

Expression of the fibroblast growth factor receptor 1 (FGFR1) gene in skeletal muscle is positively regulated in proliferating myoblasts and declines during differentiation. We have characterized the cis-regulatory elements in the proximal region of the FGFR1 promoter which render positive transcriptional activity. Multiple elements between ؊69 and ؊14 activate the FGFR1 promoter. Myoblast transfections revealed that potential Sp transcription factor binding sites are required for promoter activity. Electromobility shift assays indicated that myoblast nuclear proteins specifically bind to these cis-elements and that differentiated myotube nuclear extracts do not form these same complexes. In addition, Southwestern blot analysis detected binding of the most proximal Sp motif to a Sp1-like protein present in myoblast nuclear extracts but not in myotubes. In corroboration, Sp1 and Sp3 proteins were detected only in myoblasts and not in differentiated myotubes. Finally, transfection of Drosophila SL2 cells showed that Sp1 is a positive regulator of FGFR1 promoter activity and that Sp3 is a coactivator via the proximal Sp binding sites. These studies demonstrate that the FGFR1 promoter is activated by Sp transcription factors in proliferating myoblasts and demonstrate at least part of the mechanism by which FGFR1 gene expression is downregulated in differentiated muscle fibers.During vertebrate myogenesis, mesodermally derived cells within myogenic lineages proliferate as mononucleated myoblasts before differentiation into postmitotic, multinucleated muscle fibers. Both the sustained proliferation of myoblasts and subsequent withdrawal from the cell cycle as a part of differentiation are regulated by signal transduction cascades initiated by environmental signals including growth factors. Members of the fibroblast growth factor (FGF) 1 family of signaling molecules are capable of sustaining myoblast proliferation and delaying differentiation. The cellular effects of FGF signaling are mediated through a small family of fibroblast growth factor receptors (FGFRs). FGF1 and FGF2 possess well documented mitogenic activity for skeletal myoblasts, and these factors bind to FGFR1 in the cell surface of proliferating myoblasts. In addition to skeletal muscle myoblasts, FGFR1 is also expressed during development of the brain, skin, bones, and cardiac muscle (1). It has recently been shown that FGFR1 can be translocated to the nucleus via importin B and that it plays an important role in the regulation of the cell cycle by inducing nuclear target genes (2). However, FGF signaling declines during myoblast differentiation. This decline is the result of loss of cell surface receptor and a coordinate decrease in FGFR1 mRNA (3-5).The significance of the developmentally regulated expression of FGFR1 in relation to muscle growth and patterning in vivo has been partially examined. Myoblast differentiation and muscle fiber formation were delayed in chick limb musculature overexpressing wild type FGFR1. Conversely, premature differentiat...

show abstract

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

Section: Construction Of Mutant Plasmids-the Plasmid 3284fgfr1catmentioning

confidence: 99%

“…However, FGF signaling declines during myoblast differentiation. This decline is the result of loss of cell surface receptor and a coordinate decrease in FGFR1 mRNA (3)(4)(5).…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Sp1- and Sp3-mediated Transcriptional Regulation of the Fibroblast Growth Factor Receptor 1 Gene in Chicken Skeletal Muscle Cells

Parakati

DiMario

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

Repression of fibroblast growth factor receptor 1 gene expression by E2F4 in skeletal muscle cells

Parakati

DiMario

2004

Developmental Dynamics

View full text Add to dashboard Cite

Fibroblast growth factor receptor 1 (FGFR1) gene expression is positively and negatively regulated during muscle differentiation. We recently reported that FGFR1 gene expression was up-regulated by Sp transcription factors in proliferating myoblasts. However, the mechanism of down-regulation of this gene during differentiation is unknown. We have identified the transcription factor E2F4 as a negative regulator of FGFR1 gene expression. Immunodetection studies revealed that endogenous E2F1 and E2F2 proteins were cytoplasmic in myoblasts and myotubes, whereas E2F4 was abundant in the nuclei of both. Upon overexpression, E2F4 repressed FGFR1 promoter activity in a dose-dependent manner in myoblasts and Drosophila SL2 cells, and mutation of the E2F4 binding site increased FGFR1 promoter activity and reduced E2F4-mediated repression. Gel shift assays detected E2F4 binding to a synthetic

show abstract

Apoptosis, proliferation and gene expression patterns in mouse developing tongue

Nie

2005

Anat Embryol

View full text Add to dashboard Cite

The Fgf/Fgfr (Fgf receptor) and Bmp signal pathways are critical for embryonic development and postnatal growth. In order to address their roles in tongue development, preliminary study of expression patterns of some important members in the two families, as well as of apoptosis and proliferation, were carried out in mouse developing tongue. Apoptosis in tongue is a very late event in embryogenesis, restricted to the upper layer of the epithelium whereas proliferation is very vigorous at the early stage of tongue development and remains active throughout embryogenesis. Bmp2, -4 and -5 were localized within the mesenchyme at the early embryonic stage of tongue development (E12 to E13), whereas Bmp3 and Bmp7 were mainly expressed in the epithelium. Most of these molecules were also seen in the tongue muscles at postnatal stages. Among Fgfr isoforms, Fgfr1c, -2b, and -2c were detected in embryogenesis with peak expression at E11 to E13. Fgfr1c and Fgfr2c were localized within the mesenchyme, while Fgfr2b was mainly expressed in the epithelium. High expression of Fgf7 and Fgf10 was also detected in the mesenchyme at the early embryonic stage of tongue development, corresponding to the Fgfr expression, suggesting that they are among the principal ligands functioning at the early embryonic expanding stage. Fgf2 was seen in the tongue muscles at the late embryonic and postnatal stages. These results suggest that Bmp and Fgf signalling regulates tongue development at multiple stages, possibly related to proliferation and differentiation.

show abstract

Regulation of avian fibroblast growth factor receptor 1 (FGFR-1) gene expression during skeletal muscle differentiation

Cited by 23 publications

References 29 publications

Sp1- and Sp3-mediated Transcriptional Regulation of the Fibroblast Growth Factor Receptor 1 Gene in Chicken Skeletal Muscle Cells

Sp1- and Sp3-mediated Transcriptional Regulation of the Fibroblast Growth Factor Receptor 1 Gene in Chicken Skeletal Muscle Cells

Repression of fibroblast growth factor receptor 1 gene expression by E2F4 in skeletal muscle cells

Apoptosis, proliferation and gene expression patterns in mouse developing tongue

Contact Info

Product

Resources

About