Comparative ultrastructure of the cellular components of the unconstricted notochord in the sturgeon and the lungfish

Journal of Morphology
R J Schmitz

Abstract

Unconstricted notochords are found in only a few extant vertebrates. Within the bony fishes the notochord is present throughout life in the sturgeons and the lungfishes. To better understand the function of this organ, the cellular ultrastructure of the notochord was examined in the shortnose sturgeon, Acipenser brevirostratus, and in the African lungfish, Protopterus annectens. In both species, the medulla of the notochord consists of vacuolated cells connected by desmosomes. The vacuoles are surrounded by a dense cytoplasmic network of intermediate filaments. In Acipenser, the cuboidal to columnar basal cells are avacuolate and contain an extensive network of rough endoplasmic reticulum. In Protopterus, the cytoplasm of the basal cells lacks rough endoplasmic reticulum and often contains a large central vacuole surrounded by a network of intermediate filaments. Cells resembling fibroblasts are found in the fibrous sheath of the notochord of the lungfish, but the fibrous sheath of the sturgeon is acellular. On the basis of the structures observed in the two species, the medulla of the notochord has many of the characteristics of a keratinized epithelium, and the fibrous sheath may be derived from different cellular sources. J....Continue Reading

References

May 1, 1975·The Journal of Experimental Zoology·R W GriffithG E Pickford
Jan 1, 1991·Acta histochemica·U WelschI C Potter
Jan 1, 1991·Cell Motility and the Cytoskeleton·O Skalli, R D Goldman
Jan 1, 1989·Cell Motility and the Cytoskeleton·M W KlymkowskyA Domingo
Feb 1, 1989·Current Opinion in Cell Biology·R M Robson
Jul 2, 1973·Biochemical and Biophysical Research Communications·T F LinsenmayerJ Gross
Jun 25, 1984·Journal of Molecular Biology·E F EikenberryB Brodsky

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Citations

May 15, 2007·Developmental Dynamics : an Official Publication of the American Association of Anatomists·Di Jiang, William C Smith
Jul 7, 2015·The Anatomical Record : Advances in Integrative Anatomy and Evolutionary Biology·Ivana RestovićIvana Bočina
Apr 3, 2012·Seminars in Cell & Developmental Biology·Elsa Denker, Di Jiang

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