title: Transcriptomic profiling of host-parasite interactions in the microsporidian Trachipleistophora hominis.
abstract: BACKGROUND
  Trachipleistophora hominis was isolated from an HIV/AIDS patient and is a member of a highly successful group of obligate intracellular parasites.
  
  
  METHODS
  Here we have investigated the evolution of the parasite and the interplay between host and parasite gene expression using transcriptomics of T. hominis-infected rabbit kidney cells.
  
  
  RESULTS
  T. hominis has about 30% more genes than small-genome microsporidians. Highly expressed genes include those involved in growth, replication, defence against oxidative stress, and a large fraction of uncharacterised genes. Chaperones are also highly expressed and may buffer the deleterious effects of the large number of non-synonymous mutations observed in essential T. hominis genes. Host expression suggests a general cellular shutdown upon infection, but ATP, amino sugar and nucleotide sugar production appear enhanced, potentially providing the parasite with substrates it cannot make itself. Expression divergence of duplicated genes, including transporters used to acquire host metabolites, demonstrates ongoing functional diversification during microsporidian evolution. We identified overlapping transcription at more than 100 loci in the sparse T. hominis genome, demonstrating that this feature is not caused by genome compaction. The detection of additional transposons of insect origin strongly suggests that the natural host for T. hominis is an insect.
  
  
  CONCLUSIONS
  Our results reveal that the evolution of contemporary microsporidian genomes is highly dynamic and innovative. Moreover, highly expressed T. hominis genes of unknown function include a cohort that are shared among all microsporidians, indicating that some strongly conserved features of the biology of these enormously successful parasites remain uncharacterised.
authors.affiliation: Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK. a.k.watson@ncl.ac.uk.
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Watson
authors.affiliation: Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK. tom.williams2@ncl.ac.uk.
authors.forename: Tom A
authors.initials: TA
authors.lastname: Williams
authors.affiliation: Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK. B.A.P.Williams@exeter.ac.uk.
authors.forename: Bryony A P
authors.initials: BA
authors.lastname: Williams
authors.affiliation: Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK. K.A.Moore@exeter.ac.uk.
authors.forename: Karen A
authors.initials: KA
authors.lastname: Moore
authors.affiliation: Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK. robert.hirt@ncl.ac.uk.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hirt
authors.affiliation: Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK. martin.embley@ncl.ac.uk.
authors.forename: T Martin
authors.initials: TM
authors.lastname: Embley
mesh_terms: D000483:Alleles; D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D019295:Computational Biology / Q000379:methods; D004251:DNA Transposable Elements; D004171:Diploidy; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D005787:Gene Frequency; D022761:Gene Transfer, Horizontal; D005800:Genes, Fungal; D016681:Genome, Fungal; D054884:Host-Pathogen Interactions / Q000235:genetics*; D007313:Insecta / Q000235:genetics / Q000382:microbiology; D008018:Life Cycle Stages / Q000235:genetics; D016814:Microsporidia / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D005810:Multigene Family; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide; D012326:RNA Splicing; D011817:Rabbits; D015203:Reproducibility of Results; D014158:Transcription, Genetic; D059467:Transcriptome
chemical_list: D004251:DNA Transposable Elements