title: Gene expression and functional annotation of the human and mouse choroid plexus epithelium.
abstract: BACKGROUND
  The choroid plexus epithelium (CPE) is a lobed neuro-epithelial structure that forms the outer blood-brain barrier. The CPE protrudes into the brain ventricles and produces the cerebrospinal fluid (CSF), which is crucial for brain homeostasis. Malfunction of the CPE is possibly implicated in disorders like Alzheimer disease, hydrocephalus or glaucoma. To study human genetic diseases and potential new therapies, mouse models are widely used. This requires a detailed knowledge of similarities and differences in gene expression and functional annotation between the species. The aim of this study is to analyze and compare gene expression and functional annotation of healthy human and mouse CPE.
  
  
  METHODS
  We performed 44k Agilent microarray hybridizations with RNA derived from laser dissected healthy human and mouse CPE cells. We functionally annotated and compared the gene expression data of human and mouse CPE using the knowledge database Ingenuity. We searched for common and species specific gene expression patterns and function between human and mouse CPE. We also made a comparison with previously published CPE human and mouse gene expression data.
  
  
  RESULTS
  Overall, the human and mouse CPE transcriptomes are very similar. Their major functionalities included epithelial junctions, transport, energy production, neuro-endocrine signaling, as well as immunological, neurological and hematological functions and disorders. The mouse CPE presented two additional functions not found in the human CPE: carbohydrate metabolism and a more extensive list of (neural) developmental functions. We found three genes specifically expressed in the mouse CPE compared to human CPE, being ACE, PON1 and TRIM3 and no human specifically expressed CPE genes compared to mouse CPE.
  
  
  CONCLUSIONS
  Human and mouse CPE transcriptomes are very similar, and display many common functionalities. Nonetheless, we also identified a few genes and pathways which suggest that the CPE between mouse and man differ with respect to transport and metabolic functions.
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands.
authors.forename: Sarah F
authors.initials: SF
authors.lastname: Janssen
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands.
authors.forename: Sophie J F
authors.initials: SJ
authors.lastname: van der Spek
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands.
authors.forename: Jacoline B
authors.initials: JB
authors.lastname: Ten Brink
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands.
authors.forename: Anke H W
authors.initials: AH
authors.lastname: Essing
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands.
authors.forename: Theo G M F
authors.initials: TG
authors.lastname: Gorgels
authors.affiliation: Department of Bioinformatics, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: van der Spek
authors.affiliation: Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Nomdo M
authors.initials: NM
authors.lastname: Jansonius
authors.affiliation: Department of Clinical and Molecular Ophthalmogenetics, the Netherlands Institute for Neuroscience (NIN), Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands ; Department of Ophthalmology, Academic Medical Centre (AMC), Amsterdam, The Netherlands ; Department of Clinical Genetics, Academic Medical Centre (AMC), Amsterdam, The Netherlands.
authors.forename: Arthur A B
authors.initials: AA
authors.lastname: Bergen
mesh_terms: D000368:Aged; D000818:Animals; D043303:Aryldialkylphosphatase / Q000235:genetics; D001812:Blood-Brain Barrier; D050260:Carbohydrate Metabolism / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002831:Choroid Plexus / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D015870:Gene Expression; D053263:Gene Regulatory Networks; D006801:Humans; D007473:Ion Channels / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D023421:Models, Animal; D007703:Peptidyl-Dipeptidase A / Q000235:genetics; D013045:Species Specificity; D059467:Transcriptome
chemical_list: D002352:Carrier Proteins; D007473:Ion Channels; C586979:TRIM3 protein, mouse; D043303:Aryldialkylphosphatase; C560867:PON1 protein, mouse; D007703:Peptidyl-Dipeptidase A