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Expression of a truncated, kinase-defective TGF-beta type II receptor in mouse skeletal tissue promotes terminal chondrocyte differentiation and osteoarthritis.

Serra R, Johnson M, Filvaroff EH, LaBorde J, Sheehan DM, Derynck R, Moses HL - J. Cell Biol. (1997)

Bottom Line: Lower levels of DNIIR mRNA were detected in growth plate cartilage.It is thought to be involved in a feedback loop that signals through the periosteum/ perichondrium to inhibit cartilage differentiation.The data suggest that TGF-beta may be critical for multifaceted maintenance of synovial joints.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology and the Vanderbilt Cancer Center, Vanderbilt University, Nashville, Tennessee 37232, USA.

ABSTRACT
Members of the TGF-beta superfamily are important regulators of skeletal development. TGF-betas signal through heteromeric type I and type II receptor serine/threonine kinases. When over-expressed, a cytoplasmically truncated type II receptor can compete with the endogenous receptors for complex formation, thereby acting as a dominant-negative mutant (DNIIR). To determine the role of TGF-betas in the development and maintenance of the skeleton, we have generated transgenic mice (MT-DNIIR-4 and -27) that express the DNIIR in skeletal tissue. DNIIR mRNA expression was localized to the periosteum/perichondrium, syno-vium, and articular cartilage. Lower levels of DNIIR mRNA were detected in growth plate cartilage. Transgenic mice frequently showed bifurcation of the xiphoid process and sternum. They also developed progressive skeletal degeneration, resulting by 4 to 8 mo of age in kyphoscoliosis and stiff and torqued joints. The histology of affected joints strongly resembled human osteo-arthritis. The articular surface was replaced by bone or hypertrophic cartilage as judged by the expression of type X collagen, a marker of hypertrophic cartilage normally absent from articular cartilage. The synovium was hyperplastic, and cartilaginous metaplasia was observed in the joint space. We then tested the hypothesis that TGF-beta is required for normal differentiation of cartilage in vivo. By 4 and 8 wk of age, the level of type X collagen was increased in growth plate cartilage of transgenic mice relative to wild-type controls. Less proteoglycan staining was detected in the growth plate and articular cartilage matrix of transgenic mice. Mice that express DNIIR in skeletal tissue also demonstrated increased Indian hedgehog (IHH) expression. IHH is a secreted protein that is expressed in chondrocytes that are committed to becoming hypertrophic. It is thought to be involved in a feedback loop that signals through the periosteum/ perichondrium to inhibit cartilage differentiation. The data suggest that TGF-beta may be critical for multifaceted maintenance of synovial joints. Loss of responsiveness to TGF-beta promotes chondrocyte terminal differentiation and results in development of degenerative joint disease resembling osteoarthritis in humans.

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Localization of DNIIR mRNA in skeletal tissue. Sections of knee joints from 8-wk MT-DNIIR transgenic mice were hybridized to an 35S-labeled antisense DNIIR riboprobe (A–D). Boxes shown in A delineate the approximate locations on the joints shown in  (B–D). DNIIR expression was detected in the articular cartilage (B, white arrow), synovium (B, black arrow), and periosteum/perichondrium (C and D, black arrowhead) of transgenic mice. Representative images from analysis of two different mice are shown. In 6-mo-old  transgenic mice, DNIIR expression was detected in hyperplastic synovium (E, small, black arrow) surrounding areas of cartilage metaplasia (E, large, black arrowhead). A representative image from two separate mice is shown. No hybridization was detected in wild-type  tissue (F) or in transgenic mice with an 35S-labeled sense riboprobe (data not shown). Toluidine blue–stained bright field (A–F) and  dark field (A′–F′) images are shown. Bars: (A and F) 400 μm; (B–E) 100 μm.
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Figure 4: Localization of DNIIR mRNA in skeletal tissue. Sections of knee joints from 8-wk MT-DNIIR transgenic mice were hybridized to an 35S-labeled antisense DNIIR riboprobe (A–D). Boxes shown in A delineate the approximate locations on the joints shown in (B–D). DNIIR expression was detected in the articular cartilage (B, white arrow), synovium (B, black arrow), and periosteum/perichondrium (C and D, black arrowhead) of transgenic mice. Representative images from analysis of two different mice are shown. In 6-mo-old transgenic mice, DNIIR expression was detected in hyperplastic synovium (E, small, black arrow) surrounding areas of cartilage metaplasia (E, large, black arrowhead). A representative image from two separate mice is shown. No hybridization was detected in wild-type tissue (F) or in transgenic mice with an 35S-labeled sense riboprobe (data not shown). Toluidine blue–stained bright field (A–F) and dark field (A′–F′) images are shown. Bars: (A and F) 400 μm; (B–E) 100 μm.

Mentions: The expression of DNIIR mRNA in adult skeletal tissue was localized using in situ hybridization (Fig. 4). Sections of knee joints from wild-type and MT-DNIIR mice were hybridized to an antisense 35S-labeled riboprobe corresponding to the extracellular domain of the human TGF-β type II receptor. DNIIR mRNA expression was localized to the articular cartilage, synovium, periosteum, and perichondrium of MT-DNIIR-4 mice at 8 wk of age (Fig. 4, A–D). A low level of DNIIR mRNA was detected in the lower hypertrophic zone growth plate of transgenic mice (Fig. 4 D). At 6 mo of age, DNIIR mRNA was localized to hyperplastic synovium filling the joint space, especially near areas surrounding cartilage metaplasia (Fig. 4 E). DNIIR was also localized to the periosteum (data not shown). No hybridization was detected in sections from wild-type joints (Fig. 4 F). Hybridization was also not detected to an 35S-labeled sense probe in sections from wild-type or transgenic joints (data not shown).


Expression of a truncated, kinase-defective TGF-beta type II receptor in mouse skeletal tissue promotes terminal chondrocyte differentiation and osteoarthritis.

Serra R, Johnson M, Filvaroff EH, LaBorde J, Sheehan DM, Derynck R, Moses HL - J. Cell Biol. (1997)

Localization of DNIIR mRNA in skeletal tissue. Sections of knee joints from 8-wk MT-DNIIR transgenic mice were hybridized to an 35S-labeled antisense DNIIR riboprobe (A–D). Boxes shown in A delineate the approximate locations on the joints shown in  (B–D). DNIIR expression was detected in the articular cartilage (B, white arrow), synovium (B, black arrow), and periosteum/perichondrium (C and D, black arrowhead) of transgenic mice. Representative images from analysis of two different mice are shown. In 6-mo-old  transgenic mice, DNIIR expression was detected in hyperplastic synovium (E, small, black arrow) surrounding areas of cartilage metaplasia (E, large, black arrowhead). A representative image from two separate mice is shown. No hybridization was detected in wild-type  tissue (F) or in transgenic mice with an 35S-labeled sense riboprobe (data not shown). Toluidine blue–stained bright field (A–F) and  dark field (A′–F′) images are shown. Bars: (A and F) 400 μm; (B–E) 100 μm.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2139797&req=5

Figure 4: Localization of DNIIR mRNA in skeletal tissue. Sections of knee joints from 8-wk MT-DNIIR transgenic mice were hybridized to an 35S-labeled antisense DNIIR riboprobe (A–D). Boxes shown in A delineate the approximate locations on the joints shown in (B–D). DNIIR expression was detected in the articular cartilage (B, white arrow), synovium (B, black arrow), and periosteum/perichondrium (C and D, black arrowhead) of transgenic mice. Representative images from analysis of two different mice are shown. In 6-mo-old transgenic mice, DNIIR expression was detected in hyperplastic synovium (E, small, black arrow) surrounding areas of cartilage metaplasia (E, large, black arrowhead). A representative image from two separate mice is shown. No hybridization was detected in wild-type tissue (F) or in transgenic mice with an 35S-labeled sense riboprobe (data not shown). Toluidine blue–stained bright field (A–F) and dark field (A′–F′) images are shown. Bars: (A and F) 400 μm; (B–E) 100 μm.
Mentions: The expression of DNIIR mRNA in adult skeletal tissue was localized using in situ hybridization (Fig. 4). Sections of knee joints from wild-type and MT-DNIIR mice were hybridized to an antisense 35S-labeled riboprobe corresponding to the extracellular domain of the human TGF-β type II receptor. DNIIR mRNA expression was localized to the articular cartilage, synovium, periosteum, and perichondrium of MT-DNIIR-4 mice at 8 wk of age (Fig. 4, A–D). A low level of DNIIR mRNA was detected in the lower hypertrophic zone growth plate of transgenic mice (Fig. 4 D). At 6 mo of age, DNIIR mRNA was localized to hyperplastic synovium filling the joint space, especially near areas surrounding cartilage metaplasia (Fig. 4 E). DNIIR was also localized to the periosteum (data not shown). No hybridization was detected in sections from wild-type joints (Fig. 4 F). Hybridization was also not detected to an 35S-labeled sense probe in sections from wild-type or transgenic joints (data not shown).

Bottom Line: Lower levels of DNIIR mRNA were detected in growth plate cartilage.It is thought to be involved in a feedback loop that signals through the periosteum/ perichondrium to inhibit cartilage differentiation.The data suggest that TGF-beta may be critical for multifaceted maintenance of synovial joints.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology and the Vanderbilt Cancer Center, Vanderbilt University, Nashville, Tennessee 37232, USA.

ABSTRACT
Members of the TGF-beta superfamily are important regulators of skeletal development. TGF-betas signal through heteromeric type I and type II receptor serine/threonine kinases. When over-expressed, a cytoplasmically truncated type II receptor can compete with the endogenous receptors for complex formation, thereby acting as a dominant-negative mutant (DNIIR). To determine the role of TGF-betas in the development and maintenance of the skeleton, we have generated transgenic mice (MT-DNIIR-4 and -27) that express the DNIIR in skeletal tissue. DNIIR mRNA expression was localized to the periosteum/perichondrium, syno-vium, and articular cartilage. Lower levels of DNIIR mRNA were detected in growth plate cartilage. Transgenic mice frequently showed bifurcation of the xiphoid process and sternum. They also developed progressive skeletal degeneration, resulting by 4 to 8 mo of age in kyphoscoliosis and stiff and torqued joints. The histology of affected joints strongly resembled human osteo-arthritis. The articular surface was replaced by bone or hypertrophic cartilage as judged by the expression of type X collagen, a marker of hypertrophic cartilage normally absent from articular cartilage. The synovium was hyperplastic, and cartilaginous metaplasia was observed in the joint space. We then tested the hypothesis that TGF-beta is required for normal differentiation of cartilage in vivo. By 4 and 8 wk of age, the level of type X collagen was increased in growth plate cartilage of transgenic mice relative to wild-type controls. Less proteoglycan staining was detected in the growth plate and articular cartilage matrix of transgenic mice. Mice that express DNIIR in skeletal tissue also demonstrated increased Indian hedgehog (IHH) expression. IHH is a secreted protein that is expressed in chondrocytes that are committed to becoming hypertrophic. It is thought to be involved in a feedback loop that signals through the periosteum/ perichondrium to inhibit cartilage differentiation. The data suggest that TGF-beta may be critical for multifaceted maintenance of synovial joints. Loss of responsiveness to TGF-beta promotes chondrocyte terminal differentiation and results in development of degenerative joint disease resembling osteoarthritis in humans.

Show MeSH
Related in: MedlinePlus