ISSN:
1615-6102
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Long, rigid, rod-like structures found in the culture medium of several marine dinoflagellates are shown in this report to have fine transverse bandings characteristic of extruded trichocysts. These structures in genera such asGonyaulax are believed to pass through the heavily plated surface via narrow pores. In the resting or “charged” form, trichocysts are found to have an elaborate crystalline core connected by a series of fibers and still finer fibrils to the apex of an enclosing sac. The walls of this sac consist of a single membrane and fine thread-like hoops or spirals. The design of the whole charged trichocyst is suggestive of a mechanical sensing device. Trichocysts are found to originate in membrane-limited vesicles which are localized within a spherical shell composed of Golgi bodies. Initially these vesicles contain homogeneous materials, but with increasing development a crystal lattice appears and ultimately the resting trichocyst core evolves. At this point the trichocyst leaves the Golgi area and migrates elsewhere in the cytoplasm. The charged trichocyst core is found to be waterbut not acetone-soluble in contrast to the discharged trichocyst which is unaffected by either solvent. These facts together with the finding of shafts apparently polymerizing from amorphous contents are interpreted as supporting the hydration theory of trichocyst discharge. Finally, the striking similarities between the origin and structure of extruded trichocyst shafts and the origin and structure of collagen fibers are discussed briefly.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01247920
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