scholarly journals Murine fibromodulin: cDNA and genomic structure, and age-related expression and distribution in the knee joint

2001 ◽  
Vol 355 (3) ◽  
pp. 577-585 ◽  
Author(s):  
Anna-Marja K. SÄÄMÄNEN ◽  
Heli J. SALMINEN ◽  
A. Juho RANTAKOKKO ◽  
Dick HEINEGÅRD ◽  
Eero I. VUORIO

The genomic structure of murine fibromodulin was determined, and its age-related expression and distribution were characterized in knee epiphyses, with decorin studied for reference. Fibromodulin, as well as decorin, have roles in collagen fibrillogenesis both in vitro and in vivo. The murine fibromodulin gene, Fmod, was similar with that in other species, with three exons and 86% of the translated sequence in exon 2. The 2.7kb long cDNA contains an open reading frame of 1131nt. Fibromodulin mRNA levels were highest in tissues rich in fibrillar collagens type I or type II. During growth, the distribution of fibromodulin mRNA was similar with that of type II collagen, with the highest levels between 5 days and 1 month of age. Thereafter, the expression of type II collagen declined to a level near the detection limit, whereas the fibromodulin expression decreased less markedly to a level of approx. 35% of maximum, and remained constant throughout the rest of the observation period. In contrast, decorin mRNA levels were the highest in old animals. Pericellular deposition of fibromodulin was strong around the late-hypertrophic chondrocytes of the secondary ossification centre and in the growth plate. In young epiphyses, both fibromodulin and decorin were found interterritorially, mainly in the uncalcified and deep-calcified cartilage. In the old mice, calcified cartilage became enriched with regard to fibromodulin, while, in contrast, decorin deposition diminished, particularly near the tidemark. In the subchondral bone trabeculae, decorin was found in the endosteum of growing, but not in the mature, epiphyses. Differences in the expression and distribution profiles suggest different roles for fibromodulin and decorin in the regulation of collagen fibrillogenesis, maintenance of the fibril organization and matrix mineralization. As fibromodulin is deposited closer to cells than decorin, it may have a primary role in collagen fibrillogenesis, whereas decorin might be involved in the maintenance of fibril structures in the interterritorial matrix.

2000 ◽  
Vol 345 (2) ◽  
pp. 377-384 ◽  
Author(s):  
Constance M. YUAN ◽  
Leena ALA-KOKKO ◽  
Dominique LE GUELLEC ◽  
Suzanne FRANC ◽  
Andrzej FERTALA ◽  
...  

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.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jin Young Ko ◽  
Hayoung Kim ◽  
Joonyoung Jang ◽  
Jun Chang Lee ◽  
Ju Seok Ryu

AbstractAge-related weakness due to atrophy and fatty infiltration in oropharyngeal muscles may be related to dysphagia in older adults. However, little is known about changes in the oropharyngeal muscle activation pattern in older adults. This was a prospective and experimental study. Forty healthy participants (20 older [> 60 years] and 20 young [< 60 years] adults) were enrolled. Six channel surface electrodes were placed over the bilateral suprahyoid (SH), bilateral retrohyoid (RH), thyrohyoid (TH), and sternothyroid (StH) muscles. Electromyography signals were then recorded twice for each patient during swallowing of 2 cc of water, 5 cc of water, and 5 cc of a highly viscous fluid. Latency, duration, and peak amplitude were measured. The activation patterns were the same, in the order of SH, TH, and StH, in both groups. The muscle activation patterns were classified as type I and II; the type I pattern was characterized by a monophasic shape, and the type II comprised a pre-reflex phase and a main phase. The oropharyngeal muscles and SH muscles were found to develop a pre-reflex phase specifically with increasing volume and viscosity of the swallowed fluid. Type I showed a different response to the highly viscous fluid in the older group compared to that in the younger group. However, type II showed concordant changes in the groups. Therefore, healthy older people were found to compensate for swallowing with a pre-reflex phase of muscle activation in response to increased liquid volume and viscosity, to adjust for age-related muscle weakness.


Development ◽  
1993 ◽  
Vol 117 (1) ◽  
pp. 245-251
Author(s):  
R. Quarto ◽  
B. Dozin ◽  
P. Bonaldo ◽  
R. Cancedda ◽  
A. Colombatti

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)


2006 ◽  
Vol 19 (2) ◽  
pp. 117-126 ◽  
Author(s):  
M. Sakuma ◽  
K. Hatsushika ◽  
K. Koyama ◽  
R. Katoh ◽  
T. Ando ◽  
...  

1977 ◽  
Vol 146 (3) ◽  
pp. 857-868 ◽  
Author(s):  
D E Trentham ◽  
A S Townes ◽  
A H Kang

We have found that intradermal injection of native type II collagen extracted from human, chick or rat cartilage induces an inflammatory arthritis in approximately 40% of rats of several strains whether complete Freund's adjuvant or incomplete Freund's adjuvant is used. Type I or III collagen extracted from skin, cartilage proteoglycans and alpha1(II) chains were incapable of eliciting arthritis, as was type II collagen injected without adjuvant. The disease is a chronic proliferative synovitis, resembling adjuvant arthritis in rats and rheumatoid arthritis in humans. Native type II co-lagen modified by limited pepsin digestion still produces arthritis, suggesting that type-specific determinants residing in the helical region of the molecule are responsible for the induction of disease. Since homologous type II collagen emulsified in oil without bacterial preparations regularly causes the disease, this new animal model of arthritis represents a unique example of experimentally-inducible autoimmunity to a tissue component.


Development ◽  
1988 ◽  
Vol 103 (1) ◽  
pp. 111-118 ◽  
Author(s):  
C.J. Devlin ◽  
P.M. Brickell ◽  
E.R. Taylor ◽  
A. Hornbruch ◽  
R.K. Craig ◽  
...  

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.


Author(s):  
Stefan Nehrer ◽  
Howard A. Breinan ◽  
Arun Ramappa ◽  
Sonya Shortkroff ◽  
Gretchen Young ◽  
...  
Keyword(s):  
Type I ◽  

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