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Pleodorina starrii

Pleodorina starrii
Scientific classification Edit this classification
Clade: Viridiplantae
Division: Chlorophyta
Class: Chlorophyceae
Order: Chlamydomonadales
Family: Volvocaceae
Genus: Pleodorina
Species:
P. starrii
Binomial name
Pleodorina starrii

Pleodorina starrii is a species of algae that resides in freshwater in Japan.[1] The name starri is in honor of phycologist Richard C. Starr.[2]

Since 2006 it has provided molecular genetic evidence for an evolutionary link between sexes and mating types. It was later confirmed to be the first reportedly trioecious haploid species.

Reproduction

It is trioecious meaning males, females, and hermaphrodites exist in the species.[3]

Reproduction is asexual under normal conditions and creates colonies of clones with the same genotype.[4][5] Sexual reproduction is induced by low-nitrogen conditions and is anisogamous.[1]

Studies on the species

The species was involved in a 2006 study that provided the first molecular genetic evidence for the evolutionary link between sexes and mating types.[6][7]: 215–216, 222  A male-specific gene was founded in the species and named "OTOKOGI", meaning manliness or chivalry in Japanese.[7]: 221 

The species was previously believed to be heterothallic with males and females, but a 2021 study revealed it also contained hermaphrodites.[8] This study was the first time the sexual system trioecy has been reported in haploid species and it challenged models for the evolution of sexual systems.[3] Although trioecy is viewed as being an evolutionarily unstable transitional state between dioecy and monoecy, a 2023 study revealed this probably not the case in this species. Instead, in this species, trioecy could have evolved due to the reorganization of certain genes.[2][9]

References

  1. ^ a b "Pleodorina starrii H.Nozaki, F.D.Ott & A.W.Coleman :: AlgaeBase". www.algaebase.org. Archived from the original on 30 April 2023. Retrieved 30 April 2023.
  2. ^ a b Nature, Research Communities by Springer (23 May 2023). ""Starrii" blessed us twice". Research Communities by Springer Nature. Retrieved 3 June 2024.
  3. ^ a b Roy, Scott William (November 2021). "Digest: Three sexes from two loci in one genome: A haploid alga expands the diversity of trioecious species*". Evolution. 75 (11): 3002–3003. doi:10.1111/evo.14345. ISSN 0014-3820. PMID 34486115. S2CID 237422083.
  4. ^ Nozaki, Hisayoshi (2006). "Morphology, molecular phylogeny and taxonomy of two new species of Pleodorina (Volvocaceae, Chlorophyceae)". Journal of Phycology. 42 (5): 1072–1080. Bibcode:2006JPcgy..42.1072N. doi:10.1111/j.1529-8817.2006.00255.x. S2CID 84730352. Archived from the original on 15 May 2023. Retrieved 3 June 2024.
  5. ^ "Species of algae with three sexes that all mate in pairs identified in Japanese river". EurekAlert!. Archived from the original on 1 May 2023. Retrieved 1 May 2023.
  6. ^ Nozaki, Hisayoshi; Mori, Toshiyuki; Misumi, Osami; Matsunaga, Sachihiro; Kuroiwa, Tsuneyoshi (19 December 2006). "Males evolved from the dominant isogametic mating type". Current Biology. 16 (24): R1018–1020. Bibcode:2006CBio...16R1018N. doi:10.1016/j.cub.2006.11.019. ISSN 0960-9822. PMID 17174904. S2CID 15748275.
  7. ^ a b Sawada, Hitoshi; Inoue, Naokazu; Iwano, Megumi (7 February 2014). Sexual Reproduction in Animals and Plants. Springer. pp. 215–226. ISBN 978-4-431-54589-7. Archived from the original on 3 June 2024. Retrieved 1 May 2023.
  8. ^ Takahashi, Kohei; Kawai-Toyooka, Hiroko; Ootsuki, Ryo; Hamaji, Takashi; Tsuchikane, Yuki; Sekimoto, Hiroyuki; Higashiyama, Tetsuya; Nozaki, Hisayoshi (November 2021). "Three sex phenotypes in a haploid algal species give insights into the evolutionary transition to a self-compatible mating system*". Evolution. 75 (11): 2984–2993. doi:10.1111/evo.14306. ISSN 0014-3820. PMC 9291101. PMID 34250602.
  9. ^ Takahashi, Kohei; Suzuki, Shigekatsu; Kawai-Toyooka, Hiroko; Yamamoto, Kayoko; Hamaji, Takashi; Ootsuki, Ryo; Yamaguchi, Haruyo; Kawachi, Masanobu; Higashiyama, Tetsuya; Nozaki, Hisayoshi (9 June 2023). "Reorganization of the ancestral sex-determining regions during the evolution of trioecy in Pleodorina starrii". Communications Biology. 6 (1): 590. doi:10.1038/s42003-023-04949-1. ISSN 2399-3642. PMC 10256686. PMID 37296191.