On the pathway of mineral deposition in larval zebrafish caudal fin bone.
A poorly understood aspect of bone biomineralization concerns the mechanisms whereby ions are sequestered from the environment, concentrated, and deposited in the extracellular matrix. In this study, we follow mineral deposition in the caudal fin of the zebrafish larva in vivo. Using fluorescence and cryo-SEM-microscopy, in combination with Raman and XRF spectroscopy, we detect the presence of intracellular mineral particles located between bones, and in close association with blood vessels. Calcium-rich particles are also located away from the mineralized bone, and these are also in close association with blood vessels. These observations challenge the view that mineral formation is restricted to osteoblast cells juxtaposed to bone, or to the extracellular matrix. Our results, derived from observations performed in living animals, contribute a new perspective to the comprehensive mechanism of bone formation in vertebrates, from the blood to the bone. More broadly, these findings may shed light on bone mineralization processes in other vertebrates, including humans.
Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Anat
A
Akiva
Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
Guy
G
Malkinson
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Admir
A
Masic
Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Michael
M
Kerschnitzki
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Mathieu
M
Bennet
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Peter
P
Fratzl
Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Lia
L
Addadi
Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel. Electronic address: Steve.weiner@weizmann.ac.il.
Steve
S
Weiner
Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
Karina
K
Yaniv
D000818:Animals; D002113:Calcification, Physiologic / Q000502:physiology*; D007814:Larva; D008855:Microscopy, Electron, Scanning; D010012:Osteogenesis / Q000502:physiology*; D013052:Spectrometry, X-Ray Emission; D013059:Spectrum Analysis, Raman; D015027:Zebrafish
Amorphous calcium phosphate; Biomineralization; Correlative fluorescence-Raman imaging; Cryo-SEM; In vivo imaging; Octacalcium phosphate