title: De novo assembly and transcriptome analysis of Plasmodium gallinaceum identifies the Rh5 interacting protein (ripr), and reveals a lack of EBL and RH gene family diversification.
abstract: BACKGROUND
  Malaria parasites that infect birds can have narrow or broad host-tropisms. These differences in host specificity make avian malaria a useful model for studying the evolution and transmission of parasite assemblages across geographic ranges. The molecular mechanisms involved in host-specificity and the biology of avian malaria parasites in general are important aspects of malaria pathogenesis that warrant further examination. Here, the transcriptome of the malaria parasite Plasmodium gallinaceum was characterized to investigate the biology and the conservation of genes across various malaria parasite species.
  
  
  METHODS
  The P. gallinaceum transcriptome was annotated and KEGG pathway mapping was performed. The ripr gene and orthologous genes that play critical roles in the purine salvage pathway were identified and characterized using bioinformatics and phylogenetic methods.
  
  
  RESULTS
  Analysis of the transcriptome sequence database identified essential genes of the purine salvage pathway in P. gallinaceum that shared high sequence similarity to Plasmodium falciparum when compared to other mammalian Plasmodium spp. However, based on the current sequence data, there was a lack of orthologous genes that belonged to the erythrocyte-binding-like (EBL) and reticulocyte-binding-like homologue (RH) family in P. gallinaceum. In addition, an orthologue of the Rh5 interacting protein (ripr) was identified.
  
  
  CONCLUSIONS
  These findings suggest that the pathways involved in parasite red blood cell invasion are significantly different in avian Plasmodium parasites, but critical metabolic pathways are conserved throughout divergent Plasmodium taxa.
authors.affiliation: Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA. ejlauron@wustl.edu.
authors.forename: Elvin J
authors.initials: EJ
authors.lastname: Lauron
authors.affiliation: Rheumatology Division, Washington University School of Medicine, St. Louis, MO, USA. awyeang@wustl.edu.
authors.forename: Han Xian
authors.initials: HX
authors.lastname: Aw Yeang
authors.affiliation: Rheumatology Division, Washington University School of Medicine, St. Louis, MO, USA. staffner@dom.wustl.edu.
authors.forename: Samantha M
authors.initials: SM
authors.lastname: Taffner
authors.affiliation: Department of Biology, San Francisco State University, San Francisco, CA, USA. sehgal@sfsu.edu.
authors.forename: Ravinder N M
authors.initials: RN
authors.lastname: Sehgal
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D004912:Erythrocytes / Q000469:parasitology; D020869:Gene Expression Profiling; D008289:Malaria, Avian / Q000469:parasitology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010964:Plasmodium gallinaceum / Q000235:genetics* / Q000378:metabolism*; D015800:Protozoan Proteins / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D059467:Transcriptome / Q000235:genetics*
chemical_list: D015800:Protozoan Proteins