title: Diversity of extracellular proteins during the transition from the 'proto-apicomplexan' alveolates to the apicomplexan obligate parasites.
abstract: The recent completion of high-coverage draft genome sequences for several alveolate protozoans - namely, the chromerids, Chromera velia and Vitrella brassicaformis; the perkinsid Perkinsus marinus; the apicomplexan, Gregarina niphandrodes, as well as high coverage transcriptome sequence information for several colpodellids, allows for new genome-scale comparisons across a rich landscape of apicomplexans and other alveolates. Genome annotations can now be used to help interpret fine ultrastructure and cell biology, and guide new studies to describe a variety of alveolate life strategies, such as symbiosis or free living, predation, and obligate intracellular parasitism, as well to provide foundations to dissect the evolutionary transitions between these niches. This review focuses on the attempt to identify extracellular proteins which might mediate the physical interface of cell-cell interactions within the above life strategies, aided by annotation of the repertoires of predicted surface and secreted proteins encoded within alveolate genomes. In particular, we discuss what descriptions of the predicted extracellular proteomes reveal regarding a hypothetical last common ancestor of a pre-apicomplexan alveolate - guided by ultrastructure, life strategies and phylogenetic relationships - in an attempt to understand the evolution of obligate parasitism in apicomplexans.
authors.affiliation: Department of Protozoology,Institute of Tropical Medicine (NEKKEN),Nagasaki University,1-12-4 Sakamoto,Nagasaki 852-8523,Japan.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Templeton
authors.affiliation: Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division,King Abdullah University of Science and Technology (KAUST),Thuwal,Jeddah 23955-6900,Kingdom of Saudi Arabia.
authors.forename: Arnab
authors.initials: A
authors.lastname: Pain
mesh_terms: D056893:Alveolata / Q000235:genetics* / Q000502:physiology; D000818:Animals; D016782:Apicomplexa / Q000235:genetics / Q000502:physiology; D005075:Biological Evolution; D005109:Extracellular Matrix / Q000378:metabolism; D018503:Genome, Protozoan / Q000235:genetics*; D010271:Parasites / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny; D020543:Proteome; D015800:Protozoan Proteins / Q000378:metabolism
chemical_list: D020543:Proteome; D015800:Protozoan Proteins
keywords: Alveolata; Apicomplexa; Chromera; Colpodella; Cryptosporidium; Gregarina; Perkinsus; Plasmodium; Toxoplasma; Vitrella