A widespread coral-infecting apicomplexan with chlorophyll biosynthesis genes

@article{Kwong2019AWC,
  title={A widespread coral-infecting apicomplexan with chlorophyll biosynthesis genes},
  author={Waldan K. Kwong and Javier del Campo and Varsha Mathur and Mark J. A. Vermeij and Patrick J. Keeling},
  journal={Nature},
  year={2019},
  volume={568},
  pages={103-107}
}
Apicomplexa is a group of obligate intracellular parasites that includes the causative agents of human diseases such as malaria and toxoplasmosis. Apicomplexans evolved from free-living phototrophic ancestors, but how this transition to parasitism occurred remains unknown. One potential clue lies in coral reefs, of which environmental DNA surveys have uncovered several lineages of uncharacterized basally branching apicomplexans1,2. Reef-building corals have a well-studied symbiotic relationship… 

Taxonomy of the Apicomplexan Symbionts of Coral, including Corallicolida ord. nov., Reassignment of the Genus Gemmocystis, and Description of New Species Corallicola aquarius gen. nov. sp. nov. and Anthozoaphila gnarlus gen. nov. sp. nov.

TLDR
Phylogenetic analyses confirm that these organisms fall into a discrete deep‐branching clade within the Apicomplexa not closely related to any known species or major subgroup, and assign this clade to a new order, Corallicolida ord. nov.

Taxonomy of the apicomplexan symbionts of coral, including Corallicolida ord. nov., reassignment of the genus Gemmocystis, and description of new species Corallicola aquarius gen. nov. sp. nov. and Anthozoaphila gnarlus gen. nov. sp. nov

Corals (Metazoa; Cnidaria; Anthozoa) have recently been shown to play host to a widespread and diverse group of intracellular symbionts of the phylum Apicomplexa. These symbionts, colloquially called

A genomic view of the reef-building coral Porites lutea and its microbial symbionts

TLDR
The recovery of metagenome-assembled genomes from the coral Porites lutea, its dinoflagellate symbiont, and its bacterial and archaeal populations, enabled comparative genomic identification of functions important for host–microbe interactions and nutritional associations.

Close relationship between coral-associated Chromera strains despite major differences within the Symbiodiniaceae

TLDR
KEGG categories provide a molecular rationalization for the ubiquitous association of Cladocopium strains with Indo-Pacific reef corals and the presence of HSP20 genes may underlie the higher thermal tolerance of Chromera.

Deep-sea corals provide new insight into the ecology, evolution, and the role of plastids in widespread apicomplexan symbionts of anthozoans

TLDR
The presence of corallicolid apicomplexans in corals below the photic zone demonstrates that they are not restricted to shallow-water reefs and are more general anthozoan symbionts.

Phylogenomics Identifies a New Major Subgroup of Apicomplexans, Marosporida class nov., with Extreme Apicoplast Genome Reduction

TLDR
A new lineage of apicomplexans is proposed, which is sister to the Coccidia and Hematozoa and proposes the class Marosporida class nov, and adds a new complexity to the models of stepwise reductive evolution of genome structure and organelle function in these parasites.

There Is Treasure Everywhere: Reductive Plastid Evolution in Apicomplexa in Light of Their Close Relatives

TLDR
The evolutionary history of the apicoplast is examined, plastid metabolism in Apicomplexa and their close relatives are explored, and it is proposed that the differences among reduced plastids result from a game of endosymbiotic roulette.

Apicomplexan-like parasites are polyphyletic and widely but selectively dependent on cryptic plastid organelles

TLDR
Phylogenetic analysis reveals that apicomplexan-like parasites are polyphyletic and their similar morphologies emerged convergently at least three times, and environmental sequences of ten novel plastid lineages and structural innovations inplastid proteins confirm that plastids in apiomplexans and their relatives are widespread and share a common, photosynthetic origin.

Symbiodiniaceae-bacteria interactions: rethinking metabolite exchange in reef-building corals as multi-partner metabolic networks.

TLDR
It is proposed that similar associations with bacterial consortia regulate Symbiodiniaceae productivity and are in turn central to the health of corals, and underpins the coral holobiont's nutrition, stress tolerance, and potentially influences the future survival of coral reefs under changing environmental conditions.

Single symbiotic cell transcriptome sequencing of coral.

...

References

SHOWING 1-10 OF 61 REFERENCES

Global diversity and distribution of close relatives of apicomplexan parasites

TLDR
Investigating the global distribution and inferred ecology of the ARLs by expansively searching for apicomplexan-related plastid small ribosomal subunit (SSU) genes in large-scale high-throughput bacterial amplicon surveys revealed ARL-V is the most diverse, geographically widespread and abundant of all ARL clades and is strictly associated with coral tissue and mucus.

Environmental distribution of coral-associated relatives of apicomplexan parasites

TLDR
The evidence points to a specific relationship between ARL-V and corals, and is suggestive of symbiosis, perhaps based on photosynthesis, in a transect between corals and associated macroalgae.

The ‘other’ coral symbiont: Ostreobium diversity and distribution

TLDR
The phylogenetic position and diversity of Ostreobium is described based on plastid 16S ribosomal DNA (rDNA), 18S rDNA and rbcL genes from a nuclear genome survey and complete plastids genome, and its environmental diversity and distribution is determined by screening the publicly available environmental data for those genes.

Deciphering the nature of the coral–Chromera association

TLDR
The transcriptional response of A. digitifera larvae leads us to conclude that Chromera could be a coral parasite, commensal, or accidental bystander, but certainly not a beneficial mutualist.

Combined Amplicon Pyrosequencing Assays Reveal Presence of the Apicomplexan “type-N” (cf. Gemmocystis cylindrus) and Chromera velia on the Great Barrier Reef, Australia

TLDR
This is the first time apicomplexan type-N has been detected in the Great Barrier Reef and the data highlight the need for combined approaches for eukaryotic diversity studies coupled with bacterial community assessment to achieve a more realistic goals of defining the holobiont community and assessing coral disease.

Cell Biology of Cnidarian-Dinoflagellate Symbiosis

TLDR
A comprehensive overview of the history of the cnidarian/coral-dinoflagellate symbiosis, its current status, and where it should be going in the future is provided.

Ubiquitous associations and a peak fall prevalence between apicomplexan symbionts and reef corals in Florida and the Bahamas

TLDR
While reef did not have a significant effect in the full model, there was a significant difference in apicomplexan prevalence between Floridian and Bahamian reefs for S. siderea, implying regional differences in this host species.

Chromerid genomes reveal the evolutionary path from photosynthetic algae to obligate intracellular parasites

TLDR
Insight is provided into how obligate parasites with diverse life strategies arose from a once free-living phototrophic marine alga, and co-regulated with genes encoding the flagellar apparatus supporting the functional contribution of flagella to the evolution of invasion machinery.
...