scholarly journals Lack of a phenotype in transgenic mice aberrantly expressing COL2A1 mRNA because of highly selective post-transcriptional down-regulation

2000 ◽  
Vol 345 (2) ◽  
pp. 377-384 ◽  
Author(s):  
Constance M. YUAN ◽  
Leena ALA-KOKKO ◽  
Dominique LE GUELLEC ◽  
Suzanne FRANC ◽  
Andrzej FERTALA ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Type I Collagen ◽  
Type Ii Collagen ◽  
Type I ◽  
Mrna Levels ◽  
Type Ii ◽  
Col2a1 Gene ◽  
Type I Procollagen ◽  
Steady State Levels ◽  
Hybridization In Situ

We reported previously that a 1.9-kb 5ʹ-fragment from the human COL1A1 gene drove transcription of a promoterless human COL2A1 gene in tissues of transgenic mice that normally express the COL1A1 but not the COL2A1 gene. In the present study, we have established that the aberrant transcription of the COL2A1 gene did not produce any gross or microscopic phenotype, because the transcripts were not efficiently translated in cells that do not normally express the COL2A1 gene. In two lines of transgenic mice, the mRNA levels from the transgene were 30% to 45% of the mRNA for the proα1(I) chain of type I procollagen, the most abundant mRNA in the same tissues. Analysis of collagens extracted from skin of the transgenic mice indicated that triple-helical type II collagen, with the normal pattern of cyanogen bromide peptides, was synthesized from the transgene. However, the level of type II collagen in skin was less than 2% of the level of type I collagen. Hybridization in situ indicated the presence of mRNA for both COL2A1 and COL1A1 in the same cells. Immunofluorescence staining for type II collagen, however, was negative in the same tissues. The results, therefore, indicated that many mesenchymal cells in the transgenic mice had high steady-state levels of the homologous mRNAs for type I and type II procollagen, but only the mRNAs for type I procollagen were efficiently translated.

Collagen expression in embryonic chicken chondrocytes treated with phorbol myristate acetate

1985 ◽  
Vol 5 (6) ◽  
pp. 1415-1424
Author(s):  
M H Finer ◽  
L C Gerstenfeld ◽  
D Young ◽  
P Doty ◽  
H Boedtker
Keyword(s):  
Morphological Change ◽  
Type I Collagen ◽  
Late Phase ◽  
Tumor Promoter ◽  
Type I ◽  
Mrna Levels ◽  
Type Ii ◽  
Collagen Mrna ◽  
Type I Procollagen ◽  
Embryonic Chicken

Growth of embryonic chicken sternal chondrocytes in the presence of phorbol-12-myristate-13-acetate (PMA), a potent tumor promoter, resulted in a dramatic morphological change from spherical floating cells to adherent fibroblastic cells. This morphological change was accompanied by a quantitative switch from synthesis of cartilage-specific type II procollagen to type I procollagen. Type II procollagen mRNA levels decreased 10-fold in PMA-treated cells. Activation of type I collagen genes led to the accumulation of type I procollagen mRNA levels comparable to those of type II mRNA in these cells. However, only type I procollagen mRNA was translated. In addition to gene activation, unprocessed pro alpha 1(I) transcripts present at low levels in control chondrocytes were processed to mature mRNA species. Redifferentiation of PMA-treated chondrocytes was possible if cells were removed from PMA after the morphological change and cessation of type II procollagen synthesis but before detectable amounts of type I procollagen were synthesized. Production of type I collagen thus marks a late phase of chondrocyte "dedifferentiation" from which reversion is no longer possible. Redifferentiated cell populations contained 24-fold more pro alpha 1(II) collagen mRNA than pro alpha 1(I) collagen mRNA, but the rates of procollagen synthesis were comparable. This suggests that the PMA-mediated dedifferentiation of chondrocytes as well as their redifferentiation is under both transcriptional and posttranscriptional regulation.

scholarly journals Altered beta-actin gene expression in phorbol myristate acetate-treated chondrocytes and fibroblasts.

1985 ◽  
Vol 5 (6) ◽  
pp. 1425-1433 ◽  
Author(s):  
L C Gerstenfeld ◽  
M H Finer ◽  
H Boedtker
Keyword(s):  
Steady State ◽  
Type I Collagen ◽  
Type Ii Collagen ◽  
Tumor Promoter ◽  
Type I ◽  
Mrna Levels ◽  
Collagen Mrna ◽  
Beta Actin ◽  
Steady State Levels ◽  
Actin Mrna

Phorbol-12-myristate-13-acetate (PMA), a potent tumor promoter, was shown to have opposite effects on the cellular morphology and steady-state levels of beta-actin mRNA in embryonic chicken muscle fibroblasts and sternal chondrocytes. When fibroblasts were treated with PMA, they formed foci of densely packed cells, ceased to adhere to culture plates, and had significantly reduced levels of beta-actin mRNA and protein. Conversely, when treated with PMA, floating chondrocytes attached to culture dishes, spread out, and began to accumulate high levels of beta-actin mRNA and proteins. In the sternal chondrocytes the stimulation of the beta-actin mRNA production was accompanied by increased steady-state levels of fibronectin mRNAs and protein. These alterations were concomitant with a fivefold reduction in type II collagen mRNA and a cessation in its protein production. After fibronectin and actin mRNAs and proteins reached their maximal levels, type I collagen mRNA and protein synthesis were turned on. Removal of PMA resulted in reduced beta-actin mRNA levels in chondrocytes and in a further alteration in the cell morphology. These observed correlations between changes in cell adhesion and morphology and beta-actin expression suggest that the effect of PMA on cell shape and adhesion may result in changes in the microfilament organization of the cytoskeleton which ultimately lead to changes in the extracellular matrix produced by the cells.

Altered beta-actin gene expression in phorbol myristate acetate-treated chondrocytes and fibroblasts

1985 ◽  
Vol 5 (6) ◽  
pp. 1425-1433
Author(s):  
L C Gerstenfeld ◽  
M H Finer ◽  
H Boedtker
Keyword(s):  
Steady State ◽  
Type I Collagen ◽  
Type Ii Collagen ◽  
Tumor Promoter ◽  
Type I ◽  
Mrna Levels ◽  
Collagen Mrna ◽  
Beta Actin ◽  
Steady State Levels ◽  
Actin Mrna

Phorbol-12-myristate-13-acetate (PMA), a potent tumor promoter, was shown to have opposite effects on the cellular morphology and steady-state levels of beta-actin mRNA in embryonic chicken muscle fibroblasts and sternal chondrocytes. When fibroblasts were treated with PMA, they formed foci of densely packed cells, ceased to adhere to culture plates, and had significantly reduced levels of beta-actin mRNA and protein. Conversely, when treated with PMA, floating chondrocytes attached to culture dishes, spread out, and began to accumulate high levels of beta-actin mRNA and proteins. In the sternal chondrocytes the stimulation of the beta-actin mRNA production was accompanied by increased steady-state levels of fibronectin mRNAs and protein. These alterations were concomitant with a fivefold reduction in type II collagen mRNA and a cessation in its protein production. After fibronectin and actin mRNAs and proteins reached their maximal levels, type I collagen mRNA and protein synthesis were turned on. Removal of PMA resulted in reduced beta-actin mRNA levels in chondrocytes and in a further alteration in the cell morphology. These observed correlations between changes in cell adhesion and morphology and beta-actin expression suggest that the effect of PMA on cell shape and adhesion may result in changes in the microfilament organization of the cytoskeleton which ultimately lead to changes in the extracellular matrix produced by the cells.

scholarly journals Collagen expression in embryonic chicken chondrocytes treated with phorbol myristate acetate.

1985 ◽  
Vol 5 (6) ◽  
pp. 1415-1424 ◽  
Author(s):  
M H Finer ◽  
L C Gerstenfeld ◽  
D Young ◽  
P Doty ◽  
H Boedtker
Keyword(s):  
Morphological Change ◽  
Type I Collagen ◽  
Late Phase ◽  
Tumor Promoter ◽  
Type I ◽  
Mrna Levels ◽  
Type Ii ◽  
Collagen Mrna ◽  
Type I Procollagen ◽  
Embryonic Chicken

Growth of embryonic chicken sternal chondrocytes in the presence of phorbol-12-myristate-13-acetate (PMA), a potent tumor promoter, resulted in a dramatic morphological change from spherical floating cells to adherent fibroblastic cells. This morphological change was accompanied by a quantitative switch from synthesis of cartilage-specific type II procollagen to type I procollagen. Type II procollagen mRNA levels decreased 10-fold in PMA-treated cells. Activation of type I collagen genes led to the accumulation of type I procollagen mRNA levels comparable to those of type II mRNA in these cells. However, only type I procollagen mRNA was translated. In addition to gene activation, unprocessed pro alpha 1(I) transcripts present at low levels in control chondrocytes were processed to mature mRNA species. Redifferentiation of PMA-treated chondrocytes was possible if cells were removed from PMA after the morphological change and cessation of type II procollagen synthesis but before detectable amounts of type I procollagen were synthesized. Production of type I collagen thus marks a late phase of chondrocyte "dedifferentiation" from which reversion is no longer possible. Redifferentiated cell populations contained 24-fold more pro alpha 1(II) collagen mRNA than pro alpha 1(I) collagen mRNA, but the rates of procollagen synthesis were comparable. This suggests that the PMA-mediated dedifferentiation of chondrocytes as well as their redifferentiation is under both transcriptional and posttranscriptional regulation.

Type VI collagen expression is upregulated in the early events of chondrocyte differentiation

Development ◽  
1993 ◽  
Vol 117 (1) ◽  
pp. 245-251
Author(s):  
R. Quarto ◽  
B. Dozin ◽  
P. Bonaldo ◽  
R. Cancedda ◽  
A. Colombatti
Keyword(s):  
Suspension Culture ◽  
Type I Collagen ◽  
Type Ii Collagen ◽  
Type I ◽  
Type Ii ◽  
Type Vi Collagen ◽  
Full Spectrum ◽  
Collagen Expression ◽  
Hypertrophic Chondrocyte

Dedifferentiated chondrocytes cultured adherent to the substratum proliferate and synthesize large amounts of type I collagen but when transferred to suspension culture they decrease proliferation, resume the chondrogenic phenotype and the synthesis of type II collagen, and continue their maturation to hypertrophic chondrocyte (Castagnola et al., 1986, J. Cell Biol. 102, 2310–2317). In this report, we describe the developmentally regulated expression of type VI collagen in vitro in differentiating avian chondrocytes. Type VI collagen mRNA is barely detectable in dedifferentiated chondrocytes as long as the attachment to the substratum is maintained, but increases very rapidly upon passage of the cells into suspension culture reaching a peak after 48 hours and declining after 5–6 days of suspension culture. The first evidence of a rise in the mRNA steady-state levels is obtained already at 6 hours for the alpha 3(VI) chain. Immunoprecipitation of metabolically labeled cells with type VI collagen antibodies reveals that the early mRNA rise is paralleled by an increased secretion of type VI collagen in cell media. Induction of type VI collagen is not the consequence of trypsin treatment of dedifferentiated cells since exposure to the actin-disrupting drug cytochalasin or detachment of the cells by mechanical procedures has similar effects. In 13-day-old chicken embryo tibiae, where the full spectrum of the chondrogenic differentiation process is represented, expression of type VI collagen is restricted to the articular cartilage where chondrocytes developmental stage is comparable to stage I (high levels of type II collagen expression).(ABSTRACT TRUNCATED AT 250 WORDS)

In situ hybridization reveals differential spatial distribution of mRNAs for type I and type II collagen in the chick limb bud

Development ◽  
1988 ◽  
Vol 103 (1) ◽  
pp. 111-118 ◽  
Author(s):  
C.J. Devlin ◽  
P.M. Brickell ◽  
E.R. Taylor ◽  
A. Hornbruch ◽  
R.K. Craig ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Limb Development ◽  
Type I Collagen ◽  
Type Ii Collagen ◽  
Limb Bud ◽  
Type I ◽  
Type Ii ◽  
Mrna Accumulation ◽  
Rna Probes

During limb development, type I collagen disappears from the region where cartilage develops and synthesis of type II collagen, which is characteristic of cartilage, begins. In situ hybridization using antisense RNA probes was used to investigate the spatial localization of type I and type II collagen mRNAs. The distribution of the mRNA for type II collagen corresponded well with the pattern of type II collagen synthesis, suggesting control at the level of transcription and mRNA accumulation. In contrast, the pattern of mRNA for type I collagen remained more or less uniform and did not correspond with the synthesis of the protein, suggesting control primarily at the level of translation or of RNA processing.

Specific and selective inhibition of translation of mRNA for type II procollagen in cells of transgenic mice that synthesize type I procollagen. A possible role for endogneous antisense RNA

1996 ◽  
Vol 15 (3) ◽  
pp. 203-210
Author(s):  
Leena Ala-Kokko ◽  
Constance Yuan ◽  
Dominique Le Guellec ◽  
Suzanne Franc ◽  
Andrzej Fertala ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Antisense Rna ◽  
Selective Inhibition ◽  
Type I ◽  
Type Ii ◽  
Type I Procollagen ◽  
In Cells

scholarly journals Protective Effects of Annatto Tocotrienol and Palm Tocotrienol-Rich Fraction on Chondrocytes Exposed to Monosodium Iodoacetate

2021 ◽  
Vol 11 (20) ◽  
pp. 9643
Author(s):  
Kok-Lun Pang ◽  
Norzana Abd Ghafar ◽  
Ima Nirwana Soelaiman ◽  
Kok-Yong Chin
Keyword(s):  
Type I Collagen ◽  
Type Ii Collagen ◽  
Collagen Type I ◽  
Type I ◽  
Protective Effects ◽  
Type Ii ◽  
Chondrocyte Viability ◽  
Monosodium Iodoacetate ◽  
Α Level ◽  
Tocotrienol Rich Fraction

Background: This study aimed to compare the chondroprotective efficacy and mechanism of annatto tocotrienol (AnTT) and palm tocotrienol-rich fraction (PT3) using SW1353 chondrocytes treated with monosodium iodoacetate (MIA). Methods: The chondrocytes were incubated with AnTT or PT3 in advance or concurrently with MIA for 24 h. The viability of the cells was tested with an MTT assay. The 8-isoprostane F2-α, extracellular matrix proteins, metalloproteinase and sex-determining region Y box protein 9 (SOX9) levels were determined using immunoassays. Results: AnTT and PT3 reversed an MIA-induced decrease in chondrocyte viability when incubated together with MIA (p < 0.05). Prior incubation with both mixtures did not produce the same effects. AnTT and PT3 cotreatment could suppress 8-isoprostane F2-α level in chondrocytes exposed to MIA (p < 0.01). Co-exposure to tocotrienols and MIA increased the type II collagen/type I collagen ratio in chondrocytes (p < 0.01). In addition, the co-exposure of AnTT and MIA for 24 h significantly upregulated SOX9, type II collagen and aggrecan levels (p < 0.05), which was not observed with co-exposure of PT3 and MIA, AnTT or PT3 exposure alone. Conclusion: AnTT and PT3 could prevent a reduction in chondrocyte viability following MIA exposure by reducing oxidative stress. In addition, AnTT might induce self-repair and anabolic activities in chondrocytes challenged with MIA.

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