The ER protein TLC domain 3B2 and its enzymatic product lactosylceramide enhance chondrocyte maturation

Members of the vertebrate hedgehog gene family (HH) are involved in patterning and modulation of differentiation. Recently it has been shown that ectopic expression of HH gene family members in vivo blocks chondrocyte maturation through activation of a parathyroid hormone related peptide (PTHrP) dependent negative regulatory loop in the perichondrium. However, the direct effect of HH on chondrocyte maturation has not been tested. Here, we studied the effect of retroviral overexpression of the chicken sonic hedgehog gene (Shh) on the growth and maturation of limb bud cells in micromass cultures. Shh is neither expressed nor required for the initiation of cellular condensation in normal micromass cultures. With Shh over-expression, micromass cultures developed novel tightly whorled nodules in addition to the normal Alcian Blue positive cartilage nodules. We characterized the new nodules and showed that they are strongly positive for alkaline phosphatase, enriched in type X collagen and weakly positive for Alcian Blue staining. Shh overexpression also increased cell proliferation, but this cannot account for the formation of the new nodules. This current study shows that misexpression of Shh in in vitro chondrogenic cultures promotes characteristics of hypertrophic chondrocytes. Thus HH has two complementary functions; a direct positive effect on chondrocyte hypertrophy in the absence of PTHrP pathway, and an indirect negative feedback loop through PTHrP to prevent other less differentiated chondrocytes from becoming hypertrophic. These two complementary actions of HH coordinate the progression of cartilage maturation.

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BMP and Ihh/PTHrP signaling interact to coordinate chondrocyte proliferation and differentiation

Development ◽

10.1242/dev.128.22.4523 ◽

2001 ◽

Vol 128 (22) ◽

pp. 4523-4534 ◽

Cited By ~ 7

Author(s):

Eleonora Minina ◽

Hans Markus Wenzel ◽

Conny Kreschel ◽

Seth Karp ◽

William Gaffield ◽

...

Keyword(s):

Bone Morphogenetic Proteins ◽

Feedback Loop ◽

Bmp Signaling ◽

Signaling Systems ◽

Chondrocyte Maturation ◽

Parathyroid Hormone Related Protein ◽

Proliferation And Differentiation ◽

Mouse Limb ◽

Pthrp Expression

During endochondral ossification, two secreted signals, Indian hedgehog (Ihh) and parathyroid hormone-related protein (PTHrP), have been shown to form a negative feedback loop regulating the onset of hypertrophic differentiation of chondrocytes. Bone morphogenetic proteins (BMPs), another family of secreted factors regulating bone formation, have been implicated as potential interactors of the Ihh/PTHrP feedback loop. To analyze the relationship between the two signaling pathways, we used an organ culture system for limb explants of mouse and chick embryos. We manipulated chondrocyte differentiation by supplementing these cultures either with BMP2, PTHrP and Sonic hedgehog as activators or with Noggin and cyclopamine as inhibitors of the BMP and Ihh/PTHrP signaling systems. Overexpression of Ihh in the cartilage elements of transgenic mice results in an upregulation of PTHrP expression and a delayed onset of hypertrophic differentiation. Noggin treatment of limbs from these mice did not antagonize the effects of Ihh overexpression. Conversely, the promotion of chondrocyte maturation induced by cyclopamine, which blocks Ihh signaling, could not be rescued with BMP2. Thus BMP signaling does not act as a secondary signal of Ihh to induce PTHrP expression or to delay the onset of hypertrophic differentiation. Similar results were obtained using cultures of chick limbs. We further investigated the role of BMP signaling in regulating proliferation and hypertrophic differentiation of chondrocytes and identified three functions of BMP signaling in this process. First we found that maintaining a normal proliferation rate requires BMP and Ihh signaling acting in parallel. We further identified a role for BMP signaling in modulating the expression of Ihh. Finally, the application of Noggin to mouse limb explants resulted in advanced differentiation of terminally hypertrophic cells, implicating BMP signaling in delaying the process of hypertrophic differentiation itself. This role of BMP signaling is independent of the Ihh/PTHrP pathway.

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HiPER1, a phosphatase of the endoplasmic reticulum with a role in chondrocyte maturation

Journal of Cell Science ◽

10.1242/jcs.111.6.803 ◽

1998 ◽

Vol 111 (6) ◽

pp. 803-813

Author(s):

P.R. Romano ◽

J. Wang ◽

R.J. O'Keefe ◽

J.E. Puzas ◽

R.N. Rosier ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Growth Plate ◽

Articular Chondrocytes ◽

Signal Sequence ◽

Growth Plate Chondrocytes ◽

Chondrocyte Maturation ◽

Er Retention ◽

Alternatively Spliced ◽

Dual Label

We have previously identified and partially cloned Band 17, a gene expressed in growth plate chondrocytes transiting from proliferation to hypertrophy. We now rename this gene HiPER1, Histidine Phosphatase of the Endoplasmic Reticulum-1, based on the results reported here. HiPER1 encodes two proteins of 318 (HiPER1(318)) and 449 (HiPER1(449)) amino acids, which are 20–21% identical to a group of yeast acid phosphatases that are in the histidine phosphatase family. HiPER1(449) is significantly more abundant than HiPER1(318), correlating with the abundance of the alternatively spliced messages encoding HiPER449 and HiPER318. Anti-HiPER1 antibodies detect two proteins of 53 and 55 kDa in growth plate chondrocytes that are absent in articular chondrocytes. We confirm that the 53 and 55 kDa proteins are HiPER1(449) by heterologous expression of the HiPER1(449) coding sequence in chick embryo fibroblasts. The 53 and 55 kDa proteins are glycosylated forms of HiPER1(449), as N-glycosidase F digestion reduces these proteins to 48 kDa, the predicted size of HiPER1(449) without the N-terminal signal sequence. Immunocytochemistry demonstrates that HiPER1(449) is found in chondrocytes maturing from proliferation to hypertrophy, but is not detectable in resting zone, deep hypertrophic zone or articular chondrocytes, a distribution that is consistent with the message distribution. HiPER1(449) was predicted to localize to the lumen of endoplasmic reticulum by an N-terminal signal sequence and by the C-terminal sequence Ala-Asp-Glu-Leu, which closely matches the consensus signal for ER retention, Lys-Asp-Glu-Leu. We confirm this prediction by demonstrating colocalization of HiPER1(449) with the ER protein HSP47 using dual-label immunofluorescence. PTHrP, a peptide that prevents hypertrophy in chondrocytes, suppressed HiPER1 and HiPER1(449) expression in vitro, an observation that further supports a role for HiPER1 in chondrocyte maturation. The yeast phosphatase homology, localization to the endoplasmic reticulum and pattern of expression suggest that HiPER1 represents a previously unrecognized intracellular pathway, involved in differentiation of chondrocytes.

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MicroRNA-218 promotes early chondrogenesis of mesenchymal stem cells and inhibits later chondrocyte maturation

BMC Biotechnology ◽

10.1186/s12896-018-0496-0 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 9

Author(s):

Song Chen ◽

Zhenyu Xu ◽

Jiahua Shao ◽

Peiliang Fu ◽

Haishan Wu

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Chondrocyte Maturation

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Autotaxin (lysoPLD/NPP2) protects fibroblasts from apoptosis through its enzymatic product, lysophosphatidic acid, utilizing albumin-bound substrate

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2005.09.140 ◽

2005 ◽

Vol 337 (3) ◽

pp. 967-975 ◽

Cited By ~ 22

Author(s):

Jaehwi Song ◽

Timothy Clair ◽

Ji Heon Noh ◽

Jung Woo Eun ◽

So Yeon Ryu ◽

...

Keyword(s):

Lysophosphatidic Acid ◽

Enzymatic Product

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An essential role of discoidin domain receptor 2 (DDR2) in osteoblast differentiation and chondrocyte maturation via modulation of Runx2 activation

Journal of Bone and Mineral Research ◽

10.1002/jbmr.225 ◽

2011 ◽

Vol 26 (3) ◽

pp. 604-617 ◽

Cited By ~ 66

Author(s):

Yan Zhang ◽

Jin Su ◽

Jiangtian Yu ◽

Xin Bu ◽

Tingting Ren ◽

...

Keyword(s):

Osteoblast Differentiation ◽

Essential Role ◽

Discoidin Domain Receptor ◽

Chondrocyte Maturation ◽

Discoidin Domain Receptor 2

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Growth Plate Chondrocyte Maturation Is Regulated by Basal Intracellular Calcium

Experimental Cell Research ◽

10.1006/excr.2002.5584 ◽

2002 ◽

Vol 277 (2) ◽

pp. 233

Author(s):

Michael J Zuscik ◽

Mary D'Souza ◽

Karlene K Gunter ◽

Thomas E Gunter ◽

Regis J O'Keefe ◽

...

Keyword(s):

Intracellular Calcium ◽

Growth Plate ◽

Chondrocyte Maturation ◽

Growth Plate Chondrocyte

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Immunohistochemical Localization of Matrix Proteins in the Femoral Joint Cartilage of Growing Commercial Pigs

Veterinary Pathology ◽

10.1177/030098589202900605 ◽

1992 ◽

Vol 29 (6) ◽

pp. 514-520 ◽

Cited By ~ 28

Author(s):

S. Ekman ◽

D. Heinegård

Keyword(s):

Subchondral Bone ◽

Matrix Protein ◽

Collagen Type ◽

Immunohistochemical Localization ◽

Matrix Composition ◽

Type Ii ◽

Collagen Type Ii ◽

Chondrocyte Maturation ◽

Proliferative Zone ◽

The Matrix

The immunocytochemical localization of several matrix macromolecules, including collagen type II and proteoglycans, in the distal femoral articular-epiphyseal cartilage complex of 15 commercial pigs between the age of 6 and 18 weeks was studied. Early osteochondrotic lesions, i.e., chondronecrosis in the resting region of the growth cartilage, as well as extensions of necrotic cartilage into the subchondral bone, were present in all animals, except those 6 weeks old. A battery of antibodies were used for identification of macromolecules in the matrix at different stages of the disease. Chondrocyte involvement in the process could be studied by identifying the sequence of alterations in matrix macromolecules as the lesion developed. The immunostaining for aggrecan (large aggregating proteoglycans), cartilage oligomeric matrix protein, fibronectin, collagen type II, fibromodulin, and biglycan was more prominent in the areas of chondronecrosis, extending into the subchondral bone, than in the normal resting region. This altered pattern of matrix macromolecules resembled that of the matrix of the proliferative chondrocytes and suggests that the chondrocyte maturation had stopped in the proliferative zone. The matrix in the areas of chondronecrosis in the resting region resembled that in the normal resting region. Thus the chondronecrosis appears to have preceded alterations of the matrix composition. The antibody reactivity pattern was, however, altered in the matrix of the clustered chondrocytes in areas of chondronecrosis. Staining in these regions suggested a more prominent appearance of fibronectin and collagen type II than in the normal matrix of the resting region. These changes are suggestive of attempt to repair. The chondronecrotic areas restricted to the resting region have a matrix that is different from the matrix of the abnormal cartilage extending into the subchondral bone, which resembled the matrix of the proliferative region. Hence the osteochondrotic lesion may not start in the resting region, instead the maturation of chondrocytes seems to stop in the proliferative zone, which would result in impaired bone formation.

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