title: Expression of PROKR1 and PROKR2 in human enteric neural precursor cells and identification of sequence variants suggest a role in HSCR.
abstract: BACKGROUND
  The enteric nervous system (ENS) is entirely derived from neural crest and its normal development is regulated by specific molecular pathways. Failure in complete ENS formation results in aganglionic gut conditions such as Hirschsprung's disease (HSCR). Recently, PROKR1 expression has been demonstrated in mouse enteric neural crest derived cells and Prok-1 was shown to work coordinately with GDNF in the development of the ENS.
  
  
  RESULTS
  In the present report, ENS progenitors were isolated and characterized from the ganglionic gut from children diagnosed with and without HSCR, and the expression of prokineticin receptors was examined. Immunocytochemical analysis of neurosphere-forming cells demonstrated that both PROKR1 and PROKR2 were present in human enteric neural crest cells. In addition, we also performed a mutational analysis of PROKR1, PROKR2, PROK1 and PROK2 genes in a cohort of HSCR patients, evaluating them for the first time as susceptibility genes for the disease. Several missense variants were detected, most of them affecting highly conserved amino acid residues of the protein and located in functional domains of both receptors, which suggests a possible deleterious effect in their biological function.
  
  
  CONCLUSIONS
  Our results suggest that not only PROKR1, but also PROKR2 might mediate a complementary signalling to the RET/GFRα1/GDNF pathway supporting proliferation/survival and differentiation of precursor cells during ENS development. These findings, together with the detection of sequence variants in PROKR1, PROK1 and PROKR2 genes associated to HSCR and, in some cases in combination with RET or GDNF mutations, provide the first evidence to consider them as susceptibility genes for HSCR.
authors.affiliation: Unidad de Gestión Clínica de Genética, Reproducción y Medicina Fetal, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.
authors.forename: Macarena
authors.initials: M
authors.lastname: Ruiz-Ferrer
authors.forename: Ana
authors.initials: A
authors.lastname: Torroglosa
authors.forename: Rocío
authors.initials: R
authors.lastname: Núñez-Torres
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: de Agustín
authors.forename: Guillermo
authors.initials: G
authors.lastname: Antiñolo
authors.forename: Salud
authors.initials: S
authors.lastname: Borrego
mesh_terms: D002478:Cells, Cultured; D002675:Child, Preschool; D015331:Cohort Studies; D017615:Enteric Nervous System / Q000166:cytology / Q000378:metabolism; D005260:Female; D005768:Gastrointestinal Hormones / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D020022:Genetic Predisposition to Disease / Q000235:genetics; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000235:genetics / Q000378:metabolism; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors / Q000235:genetics / Q000378:metabolism; D006627:Hirschsprung Disease / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018613:Microscopy, Confocal; D009154:Mutation; D058953:Neural Stem Cells / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics* / Q000378:metabolism; D018000:Receptors, Peptide / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived / Q000235:genetics / Q000378:metabolism
chemical_list: C494987:GFRA1 protein, human; D005768:Gastrointestinal Hormones; D051100:Glial Cell Line-Derived Neurotrophic Factor; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D009479:Neuropeptides; C467610:PROK1 protein, human; C423608:PROK2 protein, human; C470837:PROKR1 protein, human; C470838:PROKR2 protein, human; D043562:Receptors, G-Protein-Coupled; D018000:Receptors, Peptide; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived; D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human