Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-3-14
pubmed:databankReference
pubmed:abstractText
The phylum Apicomplexa encompasses a large number of intracellular protozoan parasites, including the causative agents of malaria (Plasmodium), toxoplasmosis (Toxoplasma), and many other human and animal diseases. Apicomplexa have recently been found to contain a relic, nonphotosynthetic plastid that has attracted considerable interest as a possible target for therapeutics. This plastid is known to have been acquired by secondary endosymbiosis, but when this occurred and from which type of alga it was acquired remain uncertain. Based on the molecular phylogeny of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes, we provide evidence that the apicomplexan plastid is homologous to plastids found in dinoflagellates-close relatives of apicomplexa that contain secondary plastids of red algal origin. Surprisingly, apicomplexan and dinoflagellate plastid-targeted GAPDH sequences were also found to be closely related to the plastid-targeted GAPDH genes of heterokonts and cryptomonads, two other groups that contain secondary plastids of red algal origin. These results address several outstanding issues: (1) apicomplexan and dinoflagellate plastids appear to be the result of a single endosymbiotic event which occurred relatively early in eukaryotic evolution, also giving rise to the plastids of heterokonts and perhaps cryptomonads; (2) apicomplexan plastids are derived from a red algal ancestor; and (3) the ancestral state of apicomplexan parasites was photosynthetic.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0737-4038
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
418-26
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Nuclear-encoded, plastid-targeted genes suggest a single common origin for apicomplexan and dinoflagellate plastids.
pubmed:affiliation
Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada. nfast@interchange.ubc.ca
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't