Members of the TGF-beta superfamily appear to modulate mesenchymal differentiation, including the processes of cartilage and bone formation. Nothing is yet known about the function of the TGF-beta-related factor vgr-1, also called bone morphogenetic protein-6 (BMP-6), and only limited studies have been conducted on the most closely related factors BMP-5, osteogenic protein-1 (OP-1) or BMP-7, an...

The vertebrate body is supported by a bony skeleton, which is largely formed by endochondral ossification. To ensure normal bone growth, differentiation of chondrocytes has to be tightly regulated. One of the major regulators of this process is the growth factor Indian hedgehog (Ihh). Endochondral ossification is impaired in Ihh mutant mice due to disturbed chondrocyte proliferation and differe...

The vertebrate body is supported by a bony skeleton, which is largely formed by endochondral ossification. To ensure normal bone growth, differentiation of chondrocytes has to be tightly regulated. One of the major regulators of this process is the growth factor Indian hedgehog (Ihh). Endochondral ossification is impaired in Ihh mutant mice due to disturbed chondrocyte proliferation and differe...

The vertebrate body is supported by a bony skeleton, which is largely formed by endochondral ossification. To ensure normal bone growth, differentiation of chondrocytes has to be tightly regulated. One of the major regulators of this process is the growth factor Indian hedgehog (Ihh). Endochondral ossification is impaired in Ihh mutant mice due to disturbed chondrocyte proliferation and differe...

Adeno-associated virus (AAV) is so far the most valuable vehicle for gene therapy because it has no association with immune response and human disease. The present study was conducted to investigate the feasibility of AAV-mediated BMP4 gene transfer for bone formation. In vitro study suggested that AAV-BMP4 vectors could transduce myoblast C2C12 cells and produce osteogenic BMP4. In vivo study ...

In a recent paper inNature, Venkatesh et al. (2014) cast valuable new light on the molecular underpinnings of vertebrate evolution with their publication of the genome of the elephant shark Callorhinchus. Noting that among the gene families involved in bone formation, the SCPP family is the only one absent in Callorhinchus (and probably other chondrichthyans), they argue that this absence is pr...

Hypophosphatasia is a rare heritable disorder caused by inactivating mutations in the gene (Alpl) that encodes tissue nonspecific alkaline phosphatase (TNAP). Hypophosphatasia with onset in infants and children can manifest as rickets. How TNAP deficiency leads to bone hypomineralization is well explained by TNAP's primary function of pyrophosphate hydrolysis when expressed in differentiated bo...

The replacement of the calcified cartilage by bone tissue during the endochondral ossification of the mandibular condyle is dependent of the resorbing activity of osteoclats. After partial resorption, calcified cartilage septa are covered by a primary bone matrix secreted by osteoblasts. Osteoadherin (OSAD) is a small proteoglycan present in bone matrix but absent in cartilage during the endoch...

During skeletogenesis, cartilage develops to either permanent cartilage that persists through life or transient cartilage that is eventually replaced by bone. However, the mechanism by which cartilage phenotype is specified remains unclarified. Core binding factor alpha1 (Cbfa1) is an essential transcription factor for osteoblast differentiation and bone formation and has the ability to stimula...

During endochondral ossification, growth plate cartilage is replaced with bone. Mineralized cartilage matrix is resorbed by osteoclasts, and new bone tissue is formed by osteoblasts. As mineralized cartilage does not contain any cells, it is unclear how this process is regulated. We hypothesize that, in analogy with bone remodeling, osteoclast and osteoblast activity are regulated by osteocytes...