Extrusome

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Extrusomes are membrane-bound structures in some eukaryotes which, under certain conditions, discharge their contents outside the cell. There are a variety of different types, probably not homologous, and serving various functions.

Notable extrusomes include mucocysts, which discharge a mucous mass sometimes used in cyst formation, and trichocysts, which discharge a fibrous rod. [1] The stinging nematocysts found in Cnidarian animals may be regarded as extrusomes as well. Extrusomes found in dinoflagellates are important in the formation of red and black tides.[ citation needed ] Ancoracysta twista , a Provoran eukaryote, immobilises its prey using a type of extrusome named an ancoracyst. [2]

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References

  1. Lynn D (2008). "Glossary". The Ciliated Protozoa: Characterization, Classification, and Guide to the Literature. Springer. p. 39. ISBN   978-1-4020-8239-9 . Retrieved 16 January 2018.
  2. Janouškovec J, Tikhonenkov DV, Burki F, Howe AT, Rohwer FL, Mylnikov AP, Keeling PJ. "A New Lineage of Eukaryotes Illuminates Early Mitochondrial Genome Reduction", Current Biology 2017, doi : 10.1016/j.cub.2017.10.051