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Nephromyces Represents a Diverse and Novel Lineage of the Apicomplexa That Has Retained Apicoplasts.

ABSTRACT: A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to 1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, 2) search for the apicoplast genome of Nephromyces, and 3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the nonphotosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.

SUBMITTER: Munoz-Gomez SA

PROVIDER: S-EPMC6777426 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Nephromyces Represents a Diverse and Novel Lineage of the Apicomplexa That Has Retained Apicoplasts.

Muñoz-Gómez Sergio A SA Durnin Keira K Eme Laura L Paight Christopher C Lane Christopher E CE Saffo Mary B MB Slamovits Claudio H CH

Genome biology and evolution 20191001 10

A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to 1) find the precise phylogenetic position of Nephromyces within the Apicom ...[more]

PMID: 31328784

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Dataset Information

Nephromyces Represents a Diverse and Novel Lineage of the Apicomplexa That Has Retained Apicoplasts.

Publications

Nephromyces Represents a Diverse and Novel Lineage of the Apicomplexa That Has Retained Apicoplasts.

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