Summary
The breakdown and disappearance of γ particles was followed by electron microscopy on synchronously germinating populations of B. emersonii zoospores. The sequence of morphological changes, unaffected by the method used to induce germination, was divided into four stages. Initially, the γ particle's surrounding unit membrane becomes amorphous and buds off vesicles that fuse with the plasma membrane. Simultaneously, ca. 80 mμ vesicles are visible either partially embedded in, or lying free along, the inner surface of the electron dense matrix. These small vesicles seem to originate from a newly detected membrane system in the electron dense γ matrix. In the next stage, γ particles characteristically adhere to various organelles, especially the nuclear cap. In subsequent stages the γ particles continue to decay by releasing 80 mμ vesicles from their matrices and by budding off vesicles from their surrounding membranes. Often, multivesicular bodies are formed when the 80 mμ vesicles become enclosed by the γ particle's budding outer membrane. In the final stage, the surrounding membranes of the different particles fuse and produce large vacuoles containing many of the electron dense matrices which, though by now partially fragmented, continue to release 80 mμ vesicles. The relationship of the above events to the formation of the cell wall is discussed.
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Truesdell, L.C., Cantino, E.C. Decay of γ particles in germinating zoospores of Blastocladiella emersonii . Archiv. Mikrobiol. 70, 378–392 (1970). https://doi.org/10.1007/BF00425421
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DOI: https://doi.org/10.1007/BF00425421