Blepharisma japonicum

Blepharisma japonicum
Scientific classification
Domain: Eukaryote
(unranked): Sar
(unranked): Alveolata
Phylum: Ciliophora
Class: Heterotrichea
Order: Heterotrichida
Family: Blepharismidae
Genus: Blepharisma
Species: B. japonicum
Binomial name
Blepharisma japonicum
Suzuki, 1954

Blepharisma japonicum is a species of protozoans, that can be found either in water or soil[1] of Japan.

The body of an organism is elongated and ovoided. It has a curved anterior apex that is over the peristome. It has a cytostome which is a two-layered undulating membrane, on the right front edge, and also contractile vacuole with cytopyge terminal. It is either brown or rose-coloured.[2]

Conjugation

B. japonicum produces sexual pheromones that promote conjugation.[3][4] There are two mating types (I and II), each type excreting a specific pheromone (termed gamone 1 and gamone 2, respectively). When sexually mature mating-type I cells are moderately starved, they autonomously produce and secrete gamone I.[3] Gamone 1 specifically acts on mating-type II cells, transforming them so that they can unite with type I cells, and inducing them to secrete gamone 2. Gamone 2 then transforms type I cells so that they can unite with type II cells. Cells that can unite may then undergo conjugation. Sexual reproduction involving interaction of opposite mating types promotes outcrossing and the masking of deleterious recessive mutations in the diploid stage of the sexual cycle.[5]

References

  1. Habitat
  2. Description
  3. 1 2 Miyake, A (1981). Cell interaction by gamones in Blepharisma In: Sexual Interactions in Eukaryotic Microbes. New York: Academic Press. pp. 95–129. ISBN 978-0124312975.
  4. Sugiura M, Shiotani H, Suzaki T, Harumoto T (2010). "Behavioural changes induced by the conjugation-inducing pheromones, gamone 1 and 2, in the ciliate Blepharisma japonicum". Eur. J. Protistol. 46 (2): 143–9. doi:10.1016/j.ejop.2010.01.002. PMID 20167456.
  5. Bernstein C, Bernstein H (1997). "Sexual communication". J. Theor. Biol. 188 (1): 69–78. doi:10.1006/jtbi.1997.0459. PMID 9299310.
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