The Deep Scleroblast of the Regenerating Teleost Scale: A Model of Cell Producing a Collagenic Plywood
The teleost elasmoid scale is a collagenic tissue that is surrounded by a simple layer of cells, the scleroblasts, forming a bag in which the scale grows in surface and in thickness. A great number of thin (20 nm in diameter) randomly deposited fibrils constitutes the superficial thin layer (3 to 4 µm thick), the osseous layer, that quickly mineralizes. Large fibrils (65 nm in diameter) parallel to each other in the same layer, and each layer at angle with the other, form the fibrillary plate. This regular stack of fibrillary layers has been termed a “plywood-like” structure. In this plywood, mineralization progresses slowly, from the older superficial layers to the deep newer ones, with a distinct delay after the deposition of the organic matrix. The growth in thickness of this thick plywood (100 to 200 µm) is the result of the activity of the deep scleroblasts located at the basal surface of the scale.
KeywordsSecretory Granule Rough Endoplasmic Reticulum Golgi Complex Thin Filament Granular Endoplasmic Reticulum
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- Reith, E. J., 1968, Collagen formation in developing molar teeth of rats, J. Ultrastruct. Res., 22:383.Google Scholar
- Sire, J.-Y., and Géraudie, J., 1984, Fine structure of regenerating scales and their associated cells in the cichlid Hemichromis bimaculatus (Gill), Cell Tiss. Res., in press.Google Scholar