Junctions between early developing osteoblasts of rat calvaria as revealed by freeze-fracture and ultrathin section electron microscopy.
TLDR
Three main types of junctional structures, i.e., adherens of the macular type, gap, and focal tight junctions, coexist between osteoblasts in early developing bone and their possible involvement in early morphogenetic events is discussed.Abstract:
Although intercellular junctions have been described between mature lamellar bone cells, little has been known about junctions between osteoblasts in early developing bone. We therefore conducted a freeze-fracture and ultrathin section study on developing calvaria of rat embryos aged 17-19 days to determine what types of intercellular junctions appear between osteoblasts in early osteogenesis. We observed that three main types of junctional structures, i.e., adherens of the macular type, gap, and focal tight junctions, coexist between osteoblasts in early developing bone. Their possible involvement in early morphogenetic events is discussed. Tight junctions are considered to be involved in compartmentalization of the early matrix and final polarization of osteoblasts.read more
Citations
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Journal ArticleDOI
Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells
Rinaldo Florencio-Silva,Gisela Rodrigues da Silva Sasso,Estela Sasso-Cerri,Manuel Simões,Paulo Sérgio Cerri +4 more
TL;DR: Current data about the structure and functions of bone cells and the factors that influence bone remodeling are discussed, indicating the dynamic nature of bone tissue.
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Osteoblast differentiation and bone matrix formation in vivo and in vitro
Harry C. Blair,Quitterie C. Larrouture,Yanan Li,Hang Lin,Donna Beer-Stoltz,Li Liu,Rocky S. Tuan,Lisa J. Robinson,Paul H. Schlesinger,Deborah J. Nelson +9 more
TL;DR: The characteristics of osteoblast differentiation and bone matrix synthesis are reviewed, which reveal a sophisticated proton export network driving mineralization, a gene expression program organized with the compartmentalization of the osteooblast epithelium that produces the mature bone matrix composite, despite varying serum calcium and phosphate.
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Ultrastructure of cementum and periodontal ligament after continuous intrusion in humans: a transmission electron microscopy study.
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Morphology, Function, and Differentiation of Bone Cells
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Root resorptions in upper first premolars after application of continuous intrusive forces. Intra-individual study.
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References
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Book ChapterDOI
Structure and function of intercellular junctions.
TL;DR: This chapter reviews the morphological information on intercellular junctions derived from thin-sectioning, negative staining and freeze-cleave techniques, as well as from x-ray diffraction and biochemical investigations, and correlates the structural parameters with known or proposed physiological functions.
Journal ArticleDOI
Transforming growth factor-beta: recent progress and new challenges.
TL;DR: There has been immense progress in TGF-/~ research in the past two years and this mini-review will highlight some of these accomplishraents and indicate a few challenges for the future.
Journal ArticleDOI
Structure, function, and regulation of cellular tight junctions
E. E. Schneeberger,R. D. Lynch +1 more
TL;DR: Until the biochemical composition of this structure has been defined and its gene identified, the TJ will continue to be an elusive yet tantalizing challenge to the cell biologist.
Journal ArticleDOI
Morphological evidence of gap junctions between bone cells
TL;DR: This study used lanthanum colloid as an extracellular marker and readily penetrated the bone cell junctions and theextracellular space of bone to describe how certain small proteins circumvented the osteoblast population and rapidly penetrated the canalicular-osteocyte system.
Journal ArticleDOI
The incidence and size of gap junctions between the bone cells in rat calvaria
TL;DR: Gap junctions were detected between preosteoblast, osteoblasts, osteocytes and chondrocytes, and between these juxtaposed cell types and between some osteoclasts and overlying mononuclear cells at active sites of resorption.