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Intracellular invasion of green algae in a salamander host
Proceedings of the National Academy of Sciences (2011)
  • Ryan Kerney, Gettysburg College
  • Eunsoo Kim
  • Roger P Hangater, Indiana University
  • Aaron A Heiss, Dalhousie University
  • Cory D Bishop, St. Francis Xavier University
  • Brian K Hall, Dalhousie University
The association between embryos of the spotted salamander (Ambystoma maculatum) and green algae (“Oophila amblystomatis” Lamber ex Printz) has been considered an ectosymbiotic mutualism. We show here, however, that this symbiosis is more intimate than previously reported. A combination of imaging and algal 18S rDNA amplification reveals algal invasion of embryonic salamander tissues and cells during development. Algal cells are detectable from embryonic and larval Stages 26–44 through chlorophyll autofluorescence and algal 18S rDNA amplification. Algal cell ultrastructure indicates both degradation and putative encystment during the process of tissue and cellular invasion. Fewer algal cells were detected in later-stage larvae through FISH, suggesting that the decline in autofluorescent cells is primarily due to algal cell death within the host. However, early embryonic egg capsules also contained encysted algal cells on the inner capsule wall, and algal 18S rDNA was amplified from adult reproductive tracts, consistent with oviductal transmission of algae from one salamander generation to the next. The invasion of algae into salamander host tissues and cells represents a unique association between a vertebrate and a eukaryotic alga, with implications for research into cell–cell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures.
  • photosymbiont,
  • endosymbiosis,
  • amphibian,
  • chlorophyte
Publication Date
Citation Information
Ryan Kerney, Eunsoo Kim, Roger P Hangater, Aaron A Heiss, et al.. "Intracellular invasion of green algae in a salamander host" Proceedings of the National Academy of Sciences Vol. 108 Iss. 16 (2011)
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